@goldb would you mind sharing some tips on Graphic Design some time? That Submission is so simple yet so well done.
What do you wanna know specifically? I don't really know what to give in terms of tips. That said, when it comes to contests, I'll usually have a clear idea of what I want to do, then if I don't already know
how to do it, I'll google it.
After that I just improve by spending time trying out a bunch of different things on PS, taking your time to practise; combining parts of different skills together to make something. For example, the gradient effect I used on the badge is something I learnt while doing another promotional item, as the original was flat and wouldn't stand out in a 28x28 dimension.