Comment by Hugo Mota on "As web developers, front and back end, what 5 things do you know now, which you wished you knew when starting out?" | Hashnode
KISS is waaaaay more important than DRY. Avoid tricky maneuvers at all costs.
ALWAYS write tests if you are serious about a project.
Take time to plan the architecture of your project. Keep code related to a feature close. Keep code from different features apart.
DON'T EVER spread a feature across a bazillion of files and directories. This will make it a pain to maintain it. This is actually the same advice from the last item, but it's so important that it's wort mentioning twice.
Give priority to advices coming from experience. Some "good practices" you hear about on the internet are pure bullshit.