One issue I constantly hit with my projects is connectors. Specifically not having enough space for them. They always turn out larger than I expect.
So my quick tip of the day is to put all of the connectors in place and create the rough layout of the case/fitting. This will stop issues later on where you can’t fit everything in or can’t close the case.
For USB cables, I have some right-angled micro-USB connections which I solder onto cut down cables.