Hey there! I've been top 2% in several jams in the past and have learned a few things along the way.
First off don't over scope. I've done this almost everytime and leads to wasted content and time due to things being cut. Know your capabilities and if something is taking to long, it's ok to compromise.
Second i'd recommend coming up with a solid plan as soon as the theme is announced. You don't need to plan every aspect of your game, but know the general idea so you can effectively use your time, and if course change the plan as you go. Admittedly I've spent too much time noodling in unity.
Finally don't try to make it perfect. It's not going to be perfect, and probably not always what you imagined, but that's the fun of it for lots of people. Just let yourself compromise in code even if it's not the technically correct way.
Anyway that's my advice from my past experience. Hope that helps!









