Help with skins

[redbull57]

I am still after I don't know how long struggling to figure skins out. All the .jms, norms, and specs still confuse me like an idiot. I'm trying to put tcrains Tech 10's on xdustin513x 2017 TLD gear along with wanting to add an Atlas Air. Problem is I don't know which .jm to use because everytime I try, I end up with the gear shiny and super reflective or the boots not showing shape or the brace being messed up. Can someone please tell me how to work this so I can do this myself haha thank you