Ok This is how to install mods, There's a site called www.skydaz.com
Then goto Search box up in the right hand corner. Type what mod you want for instinks TooManyItems CJB Hacked client. Gun mod Etc. Click on it Scroll down and click Install Exe. Open up ur downloads folder when it's done downloading Run it then click Install mod And Just click no for Backup. It's useless.
Then When it's done you have the mod
Good luck Minecraft Citizens Of Pmc!