To keep the paint from chipping, make sure your color is of the best quality and durable. Second, you should choose a paint with a primer like Krylon K05150107 ColorMaster or use a primer to cover the entire surface of the item before.
Depending on the environment you will place the product, choose to paint indoors or out. However, most outdoor paints are helpful for all surfaces and minimize cracking. Alternatively, you can also protect the area you don't want to paint with masking tape.