While I applaud what you are trying to do... learn to fully control your camera... shooting strictly manually is over-hyped and somewhat silly.

For one, entry level cameras like the T6 are designed for more automated control.... they assume most users will want it because they are stepping up from a point n shoot or a camera phone where most everything was automated. Higher models give increased access to manual controls, to the point where the most advanced models (such as 7DII and 1DX) have very little in the way of "super automation".

I suggest you also learn to use Av and Tv auto exposure (AE) modes. They are very useful and in conjunction with Exposure Compensation you will still have a lot of control over the camera. To a lesser degree, Program mode can be useful too (I use it for quick shots where I just don't have time to figure things out and don't care about depth of field or have any concern about freezing or blurring subject movement).

I don't know how the T6 implements Auto ISO (if it does at all). But if it's available, that's another AE mode (even though the camera is set to M). To be useful in the real world M + Auto ISO must have user selectable upper limit and E.C. available. If the T6 doesn't offer those, I wouldn't use Auto ISO at all. I also would never use Auto ISO in conjunction with any of the other AE modes (Tv, Av & P). It's anyone's guess what might happen, and photography is all about predictability. So I'd only use Auto ISO with M.

The reason to learn to use these various AE modes is because you will run into situations where M is simply not usable... Particularly when shooting subjects in highly variable lighting conditions (i.e., intermittent clouds or when a subject is moving in and out of shadows, etc.) It pays to know how each mode works, as well as when and why to use it.

Metering modes that you've set the camera to use to determine exposure are important, too. Canon's "Evaluative Metering" works pretty darned well. That meters the entire scene, but it puts extra emphasis on the area right around active AF point(s), assuming that's where the primary subject is located. I'd suggest learning to use that meter mode first (both for M and for the AE modes). I think the T6 also offers "Center Weighted" metering, which is sort of an old-school version of Evaluative. It also meters the entire scene, but with extra emphasis on the center of the image. Some people like it. I used cameras with it for many years, but have stopped using it in lieu of Evaluative since it's been available on my Canon cameras. Evaluative works better whenever subjects aren't centered in the image.

I don't know if T6 have it, but some Canon also offer a Spot metering and Partial metering modes. These confine the metering to a narrower area (under 5% of the image for Spot, usually around 15 or 20% with Partial). Both are centered in most Canon. They can be a bit tricky to use though... requiring more careful attention to E.C., for example... but can be useful in certain situations, so are another thing to experiment with and learn how they work.

The autofocus system is the other primary thing you can control or leave more automated. Most of the time I use a single, manually selected AF point. This gives the most control over where the camera and lens focus and the highest number of in-focus shots, but is quite a bit more work for the photographer. If I recall correctly, the T6 has a 9-point AF system where only the center point is the higher performance "dual axis" or "cross" type. The rest are slower, single axis points. For that reason, you might want to emphasize using that center point most of the time (and compose your images slightly "loosely" so that you can later crop subjects off center, if you wish). Manually select and use off-center points mostly when you have "cooperative" stationary subjects. P.S. If using Spot metering, it combines well with centered Single Point. I think the T6's only other AF mode is All Points/Auto... where the camera is allowed to select the point of focus itself. Usually it will select whatever is closest and covered by an AF point.

Learn to work with Single Shot autofocus for stationary and AI Servo to track moving subjects. (AI Focus is not really another mode... it's more automation where the camera is supposed to determine if a subject is moving or not, and then use the correct mode: AI Servo or Single Shot.) I don't know if it's possible to use Back Button Focusing on a T6... That's a technique which allows AI Servo to be used full time, as one's default mode. Without BBF, AI Servo can be a problem in some situations (such as "focus and recompose"). But with it, AI Servo can be used with both moving and stationary subjects.

The difference is that Single Shot acquires focus and then stops. It will not refocus as long as you maintain half-press on the shutter release button (or press the back button, if using BBF). To refocus, you have to lift off the button and reapply. AI Servo, on the other hand, never stops and locks... it continues tracking and updating focus as long as you maintain half-press of the shutter release (or press BBF). There are advantages to this, but if you let the AF point wander off the subject (or deliberately move it off, such as with focus and recompose technique), AI Servo can cause focus errors (hence the need for BBF, where you can stop focus from changing and essentially lock it yourself, simply by lifting off the rear button).

Notice that I haven't mentioned the "Scene modes" or the full "Auto" mode. The latter is the most "point n shoot" setting of the camera... it overrides a lot (metering, exposure mode, AF mode, even the type of file you can save and whether or not the flash will fire). The preset Scene modes are similar, though they're somewhat biased in various ways for different types of subjects.... For example the "running man" sports mode will cause a faster shutter speed to be used while the "mountain" scenic mode will use a smaller aperture to make for greater depth of field. But these also dictate a lot of your settings and take much control out of your hands. I can't recall ever using them at all, on cameras that had them. (Might be a hint of sorts... the more advanced cameras don't even have Scene modes.)

If you don't already have them, you might find Bryan Peterson's "Understanding Exposure" and one of the guide books specific to the T6 very helpful. Those go into detail better than we can here and augment the user manual. Peterson's book should be a "must read" for anyone who wants to get more control of their camera!

Hope this helps!

Most DSLR's have the ability in the menu system to allow you to set how long you want the info to remain on or highlighted, LCD "on time", viewfinder "on time", meter "on time" etc. The factory defaults are generally set for the "quickie" - 4 seconds or 8, something like that. When I'm doing "slower, lazier" style of shooting, I will go in and set it to 30 seconds, or 1 minute, or whatever suits my mood. Look for it in the menu, or in the manual. I don't have a Canon DSLR (yet) so I would send you to the menu/manual.
Hope that is helpful.
mike

You don't need to use your middle finger. I never have, If you make changes to your aperture, shutter speed or ISO they will remain unchanged even if you screen goes black and you have to push the shutter button again. Besides powering the viewfinder all the half press of the shutter button does, by default, is auto focus and meter the image. It only goes black after 4 seconds of inactivity. if I have the viewfinder to my eye and am setting my cameras exposure features I rarely have 4 whole second where I am doing nothing. Perhaps the problem is your unfamiliarity with the controls and how and when to use them.

Yes, predetermine most settings looking through the viewfinder as you do. You know as I do there is NO screen on top of the camera that allows this. Most consumers buying this camera use it in an auto mode even though it works great in manual.
ISO is preset by lighting conditions. Then is shutter or aperture the priority? Set either then and from there choose the one to be variable in those 4 seconds or as you are doing hold the shutter and adjust.
I am glad you are experimenting with the camera and exploring it's use as there are so many people who just don't play around to see what does what and how it is done.
Good luck, you have an excellent camera that will provide professional level photos easily if you do your part.

Well, don't! Choose your ISO for the general light level that you have for your shooting - perhaps 100 or 200, outdoors in the sunshine. Choose a shutter speed for the action you'll be shooting - flowers & trees & landscape that'll 'hold still' for you - 1/100 or 1/200 will be fine. THEN simply adjust the f-stop until you camera indicates proper exposure. If your light level is less, adjust your ISO upward. If you're shooting more 'action'-type pix, use a shorter shutter speed. Or, if you want razor thin DOF - use a large f-stop f2, perhaps & adjust the shutter speed for correct exposure. Set, set & adjust - don't try to adjust adjust & adjust. . . you'll drive yourself crazy! To say noting that by the time ya get done 'fiddling' with your camera, what you wanted to photograph will be over & done with & something else will be happening.

Good luck & keep practicing.

Here's my suggestion.

Determine what aperture you wish to accomplish for DOF. Push the quick button and move over the F-Stop highlight and move the front wheel and adjust.
Determine your ISO and use the quick button to move over until highlighted and adjust using the front wheel.
Finally make your adjustment for the appropriate Shutter speed by using the quick dial and use the front wheel.

You may have to fine tune your exposure by increasing your shutter speed to account for motion blur and adjust ISO.

I just find it's much easier using the viewfinder for shutter speed only as a final adjustment. Set your other two adjustments with the LCD first. You can do this all through the viewfinder, but it will take some time to learn.