Eat healthy and stay positive. Don't think too much about the list of do's and dont's in first trimester as it seem a bit intimidating at a first glance. You don't need to be scared. Make sure to have a healthy lifestyle. Eat healthily, drink lots of fluids, get enough sleep, and keep yourself active. Take your prenatal vitamins and a diet rich in vital nutrients. Limit your caffeine intake and avoid eating junk foods or unhealthy foods. Avoid smoking and alcohol to keep several complications at a bay during first trimester of pregnancy.