Everyone is scared of visa rejections as they can double up the work of a student and also delay the visa process so much. It's very important for students to go through the norms and rules of the US embassy and then do everything but still here are some suggestions -
Try to do as many mock interviews as possible. Take help from different people around you. It's very important to be confident while giving your interview.
Be precise with your interviews and don't exaggerate your answers too much. Say what's needed.
Try to convey your purpose of traveling to the US. That is very important.
