Take apart the particle board piece if it is a large structure. If just working with one piece of particle board, then move on to the next step.
Use 220-grit sandpaper on a sander or by hand to sand down the entire surface of the particle board. Make sure to get every corner and edge of the particle board to create a coarse surface. There should no longer be a shine from the laminate on top of the particle board.
Wash the particle board with a tack cloth that is slightly damp. Remove all of the dust and wood particles that appeared during sanding and make sure the entire surface is clean and dry before moving on.
Apply a thin coat of primer to the particle board piece using a paint roller or brush, depending on the type of surface. Allow the primed pieces to sit and cure according to the instructions by the primer's manufacturer. Most require at least 7 days to cure before adding the top coat.
Apply the top coat of paint in one or two coats, depending on the color. Allow the particle board to dry before reassembling or using the piece again.