Contrary to how it might seem, chiptunes, the music created by hacking old Game Boys, is kind of a pain in the ass to create. If you want to do things the classic way, you'll need to track down an old Game Boy and find a flash cartridge. Once there, you've got a few different software choices, but in the case of the video below, Rainbowdragoneyes prefers to use software called Little Sound DJ.
Once you have everything up and running, you'll still need to learn how to use the software. Little Sound DJ is not exactly the easiest thing to comprehend. That's at least partially because its created using the Game Boy's interface, so everything is a bit chalky and hard to totally comprehend. It also happens to include not just a full set of 4-bit Game Boy sounds, but also a slew of drums from various kits and even advanced arpeggiators. Basically, it's got a crappy interface and a ton of different pages of options and shortened text.
Don't worry, though -- it's really not as hard as we're making it out to be. If you don't believe us, check out the video below, where Rainbowdragoneyes explains the whole program in around five minutes. The video features his song, "Creatures Ov Deception," off his newest album, Primordial Booze. It's not exactly up to even a late night infomercial quality of production, but it does offer an easy-to-understand introduction for anyone who might be interesting in delving into some minor Game Boy hacking but were afraid to start. We know we're at least a little tempted to get this going ourselves.