I am designing a mobile app and have recently watched Corbin's videos on primitives and design gallery which were super helpful (hoping you can get around the API regulations and launch 5c club), but I'm a builder not a designer. I try to use Google Stitch to help with design but don't really have a feel for what "good design" is quite yet. I can tell something's off, but not sure how to fix it. Putting a question out for anyone and everyone. How do you approach design?

I've been a long time fan and new to the community, but excited to be here! I'm wondering now that we have moved to agentic coding (looking forward to Corbin's video on Moltbot) it seems like the best way we can influence performance is by giving the best guidance and rules. Ive seen these most often in .md files. Does anyone have any best practices for a rules.md or agents.md file they would care to share?