I'm 3 years out, and over 2 years in maintenance.
Like some above, I weigh myself every morning (to make sure i'm not leaning to far above or below my happy weight range); I track everything I eat (to keep eye on caloric intake), get some exercise in (run min 5K 2-3 times a week, plus other random activities here and there: dancing, hiking, swimming).
I've figured out that at my current activity level, i can maintain my current weight at around 1800 cals a day.
Other random things I do that I *think* contribute to MY maintenance (or could just be habit now and may not actually be making a lick of difference, lol):
I try to keep bread, rice, pasta intake low. I don't completely avoid them, but they don't have main billing in my diet, or even supporting cast. More like nameless extras with non-speaking roles, lol
I make it a point to never eat to full. I may not always succeed, but I try.
I wear tight pants. Don't laugh, but having tight pants on when I go out for dinner helps to ensure that I won't overeat to over-fullness, when it's easier to do so cuz I'm just sitting around a table for hours with food, you know?
I always share desserts (or get a mini/micro one) cuz I know dessert is my downfall.
I don't eat before noon if I can help it.
If my weight goes above my happy weight range, I cut some calories until I until I'm at the bottom of said range (luckily this hasn't happened in over a year...knock on wood)
I do my running in the morning so its done and i don't get a chance to procrastinate throughout the day.
That's all i can think of at the moment, but I'm sure there are a whole bunch of other things I do....