You can actually do a pretty good job using rattlecans, but I would avoid Krylon... It never really seems to fully harden, so it always has kind of a tacky feel.

Go to an auto parts store and get touch-up paint. I think a common brand is Color-Rite. Use the same brand primer of whatever you get, otherwise the topcoat might attack the primer layer.

Give the frame a wipe down with acetone before painting; this will degrease it.

Carefully mask areas where you don't want the paint to go. Stick dowels in places like the deraileur hanger to keep those threads free of paint.

The toughest part is figuring out how and where to hang the frame while you paint it.

Wet sand with 400 grit wet-or-dry sandpaper between every coat and allow to dry. Wet sand the final coat with 1200 grit wet-or-dry, and follow it with rubbing compound.

Let it dry a few days before building it back up.

The trick with rattlecans is how thick you spray each coat. The instructions say to lightly mist. Not quite. The secret is to spray the heaviest coat that the paint will support without running or sagging. And it's a very fine line! Practice on some scrap pipe, or even cardboard, to get a feel for it.

If you're willing to go through the trouble, you can get some truly suprising results. And the bulk of the trouble is all of the wet sanding and waiting.

The other problem is the weather. Winter is the worst time of year for any kind of painting. The temperature range listed on the paint can is actually there for a reason. Unless you have a heated shop or garage (wear a respirator!), this could be the reason to have it done professionally. With this in mind, look into powdercoating. It really shouldn't cost too much, especially when you add up paint, acetone, masking tape, sandpaper, respirator/filters, rubbing compound, time...

Best of luck! And post pics when you're done!

-Erik