I second this post. Painting is a major undertaking and should not be done just to change the color. I see two reasons,
1. major corrosion or paint chips/defects
2. extremely faded colors due to sun exposure, etc.
There are videos on YouTube on how to paint an entire frame, starting with paint removal chemical, and car-grade primer, paint and clear coat. I would estimate $200 for the paints, chemicals and sanding papers/sticks, etc. There are days wait times between coats and sanding process so assume 2-3 weeks of labor before you hit with the clear coat, plus 1-2 weeks to wait for clear coat to harden before you install braze on brackets, etc.