Honestly, if someone had told me these things at the beginning I'd be in a very different place right now.
I spent months editing the wrong stuff. Obsessing over effects and transitions while the real problems - audio, pacing, workflow - were sitting there the whole time.
Here's what I'd go back and tell myself:
1. Sort your audio before anything else. I didn't prioritise this early on and it showed. People will watch a video shot on a phone. They won't sit through one where the music is louder than your voice. Noise reduction, dialogue around -6dB, music sitting well underneath. Start here. I didn't, and I wish I had.
2. Cut the pauses. My early videos were slow because I left everything in thinking it felt more natural. It doesn't. Every bit where your brain wanders as you watch it back - that bit goes. Ruthless trimming was the upgrade I made too late.
3. Rough cut the whole thing first. I used to perfect section one while the rest was still a mess. It's a trap. Get the full structure and pacing right first, then go back and add the layers.
4. Use B-roll where it actually helps. I went through a phase of adding stock footage everywhere because someone told me to. Purposeful B-roll helps. B-roll for the sake of it doesn't do what you think it does.
5. Go easy on the effects. This is the one that cost me the most wasted hours. Too many transitions, constant zooms, heavy grading. Clean editing wins. I figured that out later than I should have.
What do you wish someone had told you earlier about editing?