What can I do for cravings during pregnancy?

Healthy eating. Healthy eating and appropriate snacks. Frequent small snacks will help avoid the out of control eating. You've heard "you need what you crave". Wrong! no one needs a dozen jelly donuts or a gallon of ice cream! much still depends on discipline. Remember a few months of discipline can equal a life time without a weight struggle.
No singular fix. Obviously good diet is important. However, good hydration is very important in pregnancy. Try fluids like tea in lieu of junk foods. Finally, some people are amenable to hypnotic techniques to curb dietary indiscretions. Good luck.