How do you handle a mild bug problem?

I live on a first floor apartment in Coconut Grove Miami. The weather is hot and humid and no matter how often I clean the floor, I seem to see little ants and worms and other little bugs that make their way in constantly. I think the door may have cracks they get in throught. I do not want to call an exterminator. Will caulking work? Is their some kind of bug repeller I can spray around the front door?