I painted bicycles, motorcycles and cars when I was younger. I was lucky enough to learn to paint from my uncles. They are farmers and have made money painting cars, motorcycles and farm equipment for people during the winter after harvest. I was lucky enough to learn the process from them.
Things have changed since then though. When I learned, we used single stage paint. That is, you shot it, it was shiny and had the color. When it hardened, you polished it and it was shinier. Good stuff, but not great. These days, people shoot bicycles with urethane 2 stage paints. Paint a base coat of color and then lay down a shiny clear on top of it. The beauty of this is that the clear will seal down the stickers on the frame! The clear is also tough.
As I looked for products, my problem quite literally was volume. Paint vendors sell qty's to paint cars. Bicycles use very small volumes. Eventually I found TCP global. They sell small volumes to motorcycle customizers. Next up, I found Auto Air. This is a waterbased urethane airbrush paint that can be used for higher volume applications like motorcycle tanks and bicycle frames. Finally, I found their Kustom Klear. Shoots easily and mixes well in small volumes.
I decided to shoot the paint in a touch-up gun, and to use my trusty double action airbrush for touch up work. I've shot a lot with the airbrush and it works well. I've also shot a lot with large siphon automotive guns, but they don't do small volumes well, so I went with a gravity fed touch-up gun.
So there ya go. There is my paint and my equipment. I ended up using a standard primer, sanding papers as well as typical tapes of different types to mask the bike when ready.
My repair stand was also invaluble during the process.