Easiest for me:
(1) Don't eat sugar, grains, potatoes or beans.
If I'm not sure if something is too carby, I'll check the label and aim for a serving that is less than about 6 grams net carbs (example, a small bit of very dark chocolate).
(2) Eat only when I'm actually hungry and stop when satiated.
(3) Use butter, heavy cream, coconut oil, cream cheese, etc. liberally (very satiating).
(4) Lots of water.

Keeping it easy for a lifelong way of eating.