You should look in the Metal Gear cosplay thread, which is located in this forum as well - I think I've heard people use some sort of body suits but I 've never really looked into what goes into creating MGS4 Raiden, as I've never really been interested in cosplaying him ;^^
Good luck on your costume!
Major Ocelot - Metal Gear Solid 3 | The Boss - Metal Gear Solid 3 | Xigbar (Normal & Tweedle Dee) - Kingdom Hearts | Revolver Ocelot - Metal Gear Solid | RED fem!Spy - Team Fortress 2 | Colonel Mustard - Clue board game
Cosplay in Progress
Leonardo Da Vinci - Assassins Creed 2 | RED fem!Spy coat - Team Fortress 2
Braig - Kingdom Hearts
Sheik - LoZ (Brawl version)
Member of Oblivion Live as Xigbar