How to install Skinsrestorer?

Hello!

I just found a way to restore the skins while we are on online mode, cracked, but when I install it, i got a executable Jar file that doesn't open. How am I supposed to install Skinsrestorer?

I beg you to help me! I wan't to see my skin! I love it!

wait so, I just have to click on the jar file and start the server?

Doesn't work and I don't understand