(adsbygoogle = window.adsbygoogle || []).push({}); What do you need:
- Your *.ELF
- Fail0verflow PS3tools (precompiled) i don't have time to explain you how to compiled them.
- Linux
- Time!
- Xtse PS3Tools Key Pack
Tutorial:

1) Extract PS3tools somewhere and open a shell. make a directory called .ps3 in /home/(user)/ and extract all KEYS, inside Xtse PS3Tools Key Pack, here
2) Write in the shell cd and drag the PS3tool folder in the shell, then press ENTER
3) put your elf in the PS3tools folder
4) write in the shell ./makeself app 355 your.elf output.self (change the name of the elf if the name is different) and press enter
5) now just wait.. (it take's 15min)
6) when done look inside your folder (PS3tool folder), voilà! you sign a self

ops sorry i forget a thing KEYS

This is for SELF, not PKG lol.