I try to substitute lower calorie/fat/carb whenever possible.
For instance I use Shiratake noodles or spaghetti squash or even grated zucchini instead of pasta.
I also use plain greek yogurt in place of sour cream ALL of the time (great mixed with salsa

)
I sub out all or half cauliflower for potatoes in both mashed potatoes and even potato salad.
I add mushrooms to my meat based dishes. They have the same texture and flavor ~ nobody knows
What tricks do you use to cut calories but still eat well?