Handing in for grading

Provide a relatively complete draft version on time
It is quite common (especially for thesis projects) for your supervisor to only plan your final presentation after (s)he is satisfied that you can attain a passing grade. This way, you're not presenting in front of a crowd (of faculty, friends, and family) and then suddenly failing. It's the last thing anyone wants.
So: PLEASE ensure your supervisor can act in this way. Hand a reasonably complete draft in weeks ahead of time, so that inadequacies can still be corrected.
Read how the project will be graded
The institution likely has official guidelines on how projects such as yours are graded. E.g. a rubric detailing exactly the points on which your project will be graded. Use that!
Evaluate your own work
Look at your own project through the eyes of the reviewers. Be strict with yourself: the reviewers have more experience than you, and they will catch things you didn't see.
Focus on what the reviewers will spend most time on
In most cases, the thesis report will be read thoroughly by all reviewers. Anything that was produced in the project (e.g. software, hardware, proofs, etc.) will receive much less scrutiny from most reviewers unless there is a dedicated timeslot for this. So: making your program more pretty likely won't be noticed by most reviewers. Making your thesis more pretty will.