Camo Farming.

Camo farming in Metal Gear Solid Portable Ops plus is getting soldiers without actually killing anyone in the process. The way to do this is on Real Combat (RC) mode, create a Shooting Range game. Then you shoot the targets, but don't kill anyone. For doing this you get rewards. The rewards are sometimes not so great. But sometimes you get 'Local Soldiers'.

Local soldiers are soldiers who have a special camouflage design, which includes a map of a certain state of America. It also has the name of the state on the front. You can also get other soldiers which are only available through AP Scan and this RC reward system, such as female ocelot unit soldiers and KGBs to name a couple.

There are other ways of camo farming. Playing a capture mission on RC mode, take it in turns to capture the kerotan frog without killing people. Or so both of you get some soldiers in the same round, take in turns to stun one another. Then capture the kerotan, and you should both have some rewards.