Helldivers 2

You get more medals on high difficulty missions after the mission itself. D1 farming is usually done for Super Credits. I honestly think you should just play the game, medals are not a rare currency to come by

Some people use the FRV, I prefer the jumpack. You can use whatever you like most really.

Make sure you use recon armour, POI's will show up sooner on the compass. Also which biome you pick can be pretty important. Look for the asteroid or red desert biomes, these give you a clear line of site and are usually free of water or mountains. Water and mountains decrease the number of POI's that can spawn on a map, and that gets you less super credits. The megacities currently have next to nothing in them, but the smaller circles of urban areas have a pretty good chance to spawn POI's that have super credits in them. Bugs can have their weird spiky, hatchling ponds and no POI's can spawn in those areas, so it's best to stick with bots or squids when farming.

Honestly though, just have some fun with it. Everything I said before are the general farming tips, not the Super Laws from The Ministry of Truth. Try some different planets to see what works best for you, and try out some different load outs. You'll never find out that the R-2124 Constitution is your favorite gun if you never use it. Happy hunting Helldiver o7

Edit: I'm an idiot. I saw "farming" and just assumed it was for super credits. Medals you definitely get more medals from doing higher difficulty missions. But you can also get some pretty good chunks from the major and personal orders. Definitely do the personal orders when possible