I would make a list of your hobbies and interests and pick out skins that relate to them.
Do a process of elimination. Compare two skins at a time and decide which one is better. Eliminate the ones you like the least. That way you're not trying to compare all at once while overwhelming yourself.
You don't have to use one skin for the rest of your life. You can switch it up a bit.
Or, if you want to stick to one for the rest of your life, you can simply just make a skin that looks like you. Have it represent your identity, who you are, your culture, etc. It doesn't have to be the best skin out there or the flashiest skin. We choose characters to express ourselves, to showcase our talent, to tell others about who we are, and to be whoever we want to be.
Don't overthink it. You can change it whenever. There is no wrong choice. Follow your heart <3.
Sorry if that isn't helpful.