What is the best way to go about this?

I will most likely move to a Supercross this winter so I am not looking to spend a lot of $$$.....

Do I strip it or just sand it...........????

I would only strip it if it is chipped up really bad. If you strip it you will need a good etch primer to insure the paint will stick. Most etch primers require you to prime over them before you can paint. As you can see stripping it will cost a lot more. If you strip it you could use Sherwin Williams GBP in a spray can and probably get away with it long enough to get the suppercross. ( good bike). You can paint right over the GBP without further priming. This is not the best way but it will work. To do it right you will spend around $100.00 in paint supplies ans you will need a good spray gun and some history on how to use the gun.

Take it to reputable powdercoater like Prism who can strip it, prep it and refinish it for you and you'll never get your hands dirty.