[MrForbes]

Designing the robot before building it goes a long way to making it look good.

As mentioned, good craftsmanship and finishing the surfaces with some type of coating, are the next most important things to do.

It's tough for a rookie team to manage to make a good looking robot, so don't get discouraged if yours doesn't look as good as you'd like. Function should be top priority, and as the years go by you'll get better at integrating aesthetics into your designs.