I would actually advise against trying an x drive unless you have someone with a good level of programming knowledge to help you. An x drive is never necessary to play the game, and is really only better than a standard tank drive when you have a good driver/programmer.
instead, I would suggest you learn CAD skills. The ability to CAD a robot before you build is an extremely valuable skill, and in the long run this will do more to help you improve your build quality and design ability than any single building project will.
You can also learn a ton of valuable build quality knowledge right here on the forums, there are many topics that go into detail on building techniques.
here’s a pretty good one that’s active right now
and if you stick around and read topics you’ll definitely pick up a lot of building tips.