Net carbs is total carbs less fiber.

Stay away from rice, pasta, white bread, potatoes, and winter squash.  Eat
lots of lean meat, dairy, starchless vegetables (especially cruciates).
Stay away from fried foods.  Fresh fruits are ok in moderation; try to eat
them with the peels, as that's where most of the fiber is.  You know to stay
away from sweets.

For packaged foods, the 'lite' or 'low fat' version tends to be higher in
sugar than the 'regular'.  (When they take the fat out, it doesn't taste as
good, so they add sugar.)  Read labels carefully.

Try to get more exercise, and drink plenty of water.