Depends whether you've got a tan or not. If yes, and your skin is quite clear, you can probably lay off the foundation.
The key is to build up gradually. Start off by getting some black or brown/black mascara and some foundation that matches your skin colour (spread a tiny bit onto the back of your hand in the shop to check). Also try some clear lipgloss.
Once you've got the hang of this, go with a friend to pick out some mascara. The general rule of thumb is to go with something that brings out the colour of your eyes. Blue can look a bit eighties, so try a subtle green first.
Surprisingly, the thing that most affects the look of your face is often eyebrow shaping, rather than make-up. If you can afford it, get this done professionally the first time.