As long as you are applying the same color and type of paint, you only need to wait until the paint appears dry. You can tell if the paint is dry by examining the sheen. If it appears even, the paint is dry. If it appears shinier in certain areas, you should wait longer.
Amateur do-it-yourselfers may have a difficult time determining whether or not paint is dry. For best results, you should wait one to two hours before applying a second coat.
Once paint appears dry, it is ready for an additional coat. If you are an experienced painter, you may be able to tell if the paint is dry by examining the consistency of the sheen. If you are an inexperienced painter, you should wait one or two hours before applying a second coat. This will ensure that the paint is completely dry and ready to accept an additional coat.