iOS pros , need help!

I just installed iOS 5.1 or whatever latest version and jailbreak it wiith red sn0w. I wanted to know how I can install my own custom boot logo from my own PC that I made.

I read so many tutorials and they all show instructions how to add built in custom logos of boot logos on cydia. No. I want to add my own custom boot leg on my iphone that I made from my computer and I cant find it!