How do you wake up your PC , if it is sleeping or if it is in hibernate state.
1. BIOS
Enable WOL on your BIOS first there should be an option in your BIOS for that. Most likely you will find that option under power or network.
2. Network Card
Enable WOL (in your network cards)
3. Software Utility
Windows Users
http://www.matcode.com/wol.htm or
Mac Users
http://www.apple.com/downloads/macosx/networking_security/wakeonlan.html