A couple suggestions: pin your contest at the top of your territory and promote it in the Saloon. Just a post saying hey guys I am running this contest, you can win some sats if you are interested in joining. Doesn't have to be seen as spammy. People appreciate a heads up to something that provides them value.

They can be take up a decent amount of time. I recommend brainstorming how to run your contests with the community before running them.

Hey, thanks for mentioning ~Design, our ODCs and FUCs are not competitions, are challenges, personal challenges if you like, with a totally different approach. As OpenDesign initiative, it will stay and continue being that way. A way to contribute in a V4V manner, without knowing if your work is going to be appreciated or not. So whatever you posted there is at the service and use of the community and whoever would like to use it. If your work provides no value, you'll get no value back.

Anyhow, there has been some trial with the weekly Monday Muse bounty contest. (just released another -maybe last- one just now!) Haven't seen much participation, one had to be cancelled for lack of creativity! Maybe the reward amount is too low so quality of the submissions equals to it? But if higher should then, a much stricter criterion to evaluate ideas and required PoW be applied?