Yeah the just do it attitude is essential!
At first you suck (like anything you do for the first time) but then it gets better, if you focus on where you're going it doesn't really matter too much where you are right now.
If you're painting skeletons I'd suggest getting some two-part epoxy and make little pieces for them, just to make them different (a helmet, shin guards, one-sided spaulders) that way you have more places to use paint other than "whitish beige".