It took a few tries, and I started off easy with the bed making, then building on that. It's not so hard to make yourself make your bed or drink some water. Then when I'd gotten a couple of those down as a regular thing, it was just a bit of reflection - 'well I didn't really feel like making the bed or walking to the kitchen all those days, but now that I do it it doesn't really matter if I want to. I guess eventually push-ups will work the same'

Turns out pretty much everything works the same. Maybe the trick is that I didn't really do anything that wasn't incremental, just a day at a time, but you just kind of keep going with the momentum.

Now I tend to just do that reflexively because it's just worked so many times in so many different areas.

I would like to expand on atroyn's reply: Every choice you ever make is self-reinforcing.

If you choose to do the "right" thing or the "wrong" thing in any given moment, that will reinforce your tendency to either persevere or to give up, in the future.

So while some moments of decision may seem more important than others (with obvious / immediate consequences), these moments are in fact all supremely important.

Over time these decisions solidify into habits and character traits. Ultimately, they will determine your fate in life.