Any advice you’ve ever heard or given. I linked a great video that I think would be my answer, combined with the “stop caring what other people think about you” and “comparison is the thief of joy” comments below. Just do stuff that you wanna do, don’t compare and don’t care what others say. It’s awesome advice.
Never loan anyone anything unless you’re willing to give it to them, because that could well turn out to be exactly what you’re doing.
ETA another one that just came to me, that I’ve always liked because it’s a witty turn of phrase in addition to being useful:
If you’re doing something that leads you to wonder if you should have some safety gear (gloves, particle mask, hearing protection, etc.), then the answer is “Yes.”