How do I paint metal chairs?

Use one of the many wonderful spray paints. You can get the exact one if you go to your local DIY or craft store and ask the experts.

Rustoleum spray paint for metal comes in many metallic colors and can be purchased at any hardware store like Home Depot and Lowes. If there are any upholstered seats or chair backs remove them first. Take them outside or in a garage, put down a tarp and prep them by wiping them down and lightly sand with 0000 steel wool to remove any sheen. Wipe down to remove any dust from sanding then you are ready to start painting. Wear some gloves and a paper mask and spray three or more light coats to avoid drips. Start with the underside first and let that dry between each coat. Then turn them over and do the top and sides the same way. Check for any touch ups needed, let dry for 6 hours or overnight. Put the seats back on and bring back inside. Glass goes back on and you are done. It is as easy as that. Best wishes!

Spray paint is your best bet. Try to do it outside but if you can't, make sure you've got a lot of ventilation going and cover things around it with tarps as the paint gets everywhere.