To get the infinite ammo you have to fully upgrade a weapon to the max on everything and then beat the game. Then you have to go to bounes and purchase them with the points extra points that you earn in the game. For the outfits you have to beat the game to get Chris Safari and Sheva Clubbin and then you have to go to bounes and purchase them. For Chris STARS and Sheva Tribal you have to beat the game and obtain 25 and 30 BSAA emblems to unlock them for purchase in the bounes. For Chris Warrior, Chris Heavy Metal, Sheva Business, and Sheva Fairytale you have to purchase the costume packs from the XBLA marketplace or the PSN store or buy the UNTOLD STORIES from the XBLA marketplace or the PSN store. To use the infinie ammo you have to go under the special settings and then choose the infinie ammo section. Then all you have to do is to turn on infintie ammo and then turn infinite ammo on again when you choose a chapter to play on. For the costumes you have to go under special settings again and choose Costumes. Choose the cotumes for the characters and then exit and choose a chapter to play in to and then bingo, you are playing in extra costumes.
ALTERNATE INFINTE AMMO: For the alternate way to get infinte ammo you have to go through the chapters you beat to earn money. Once you earn some money you have to upgrade 2 of the guns you may already have. You have to fully upgrade the VZ61 to get the gatling gun and the S75 sinper rifle to get the longbow. Both weapons have to be purchase with the money you collected as well, and both will cost you 100,000 money to buy, which is 50,000 for each of them. Both have unlimited ammo, but both have flaws with them. The gatling gun is not accurate and has low stopping power and the long bow has no laser or sights.