u/Glittering-Most-2951

I’ve been collecting for about two months now. So far I’ve mostly been buying loose packs and picking up higher-end cards on Whatnot. I haven’t sold anything yet because I’m still learning the hobby.
For those of you who’ve been doing this for a while, what advice would you give a beginner? Anything you wish you knew when you first started collecting or selling? Any common mistakes to avoid?