Day 25: Create a backup of your project!
This should be one of the very first steps you should do when starting with your game’s development: create a backup of your project, if possible, online. I remember a lot of cases with my friends and colleagues in the M.U.G.E.N. forums, where suddenly, they’d lost all their progress made over months and even years of work, and they’d have no backup to continue, which made them lose motivation to rework everything again. For Redd’s Runaway, it took me more time than what I’d like (even if nothing wrong happened), so don’t make the same mistake with your game.
Services like Github or Dropbox can be helpful for this task, and there are plenty of tutorials available to help you through every step. If you have good progress right now in your game but don’t have a backup set already, take at least one day to create your backup before it is too late to recover your work.