Choose the type of paint first. There are many types but not all of them will adapt well to the addition of sparkles. In oil-based paint it will need to be stirred to distribute the sparkles evenly right before painting. Latex paint comes in thick and thin consistency and the thick type works better with sparkles.
Add the sparkles right before painting so they do not have time to sink to the bottom of the paint can. If this starts to happen, quickly pour the paint into a tray and use a roller for a smoother effect. Let dry. Latex paint dries more quickly than oil-based paints. On average, latex paint takes about two hours to dry. Oil-based paint should be allowed to dry overnight.
Use a clear acrylic sealer coat over the dry paint. It will seal in the sparkles so that they do not chip off or shed. Let the sealant dry for one hour.