Superpilot, my advices for 747dreamliner stand for your case also.
Try to have some relative health exams (inner ear & stomach) to eliminate any health issues.
If there aren't any, try not to think about it as you fly (i know it's very difficult if it happened to you more than once) by flying the plane as much as you can (keeping your mind task filled will not allow it to think about nausea).
Finally, "DON'T GO SOLO UNTIL YOU OVERCOME THE PROBLEM".
I can not overemphasize this last advice.