Turn the screws at the top of the drop-side guide rails counterclockwise to remove them from the crib assembly. You may want to ask someone to help you with this process since once you do this, the front of the crib will no longer be secured in place and can fall.
Remove the drop-side guide rails by pulling them up through the front panel of the crib. As you do this, you will want to remove the springs from the drop-side rail so they don't get lost.
Remove the L-brackets from the front legs of the crib. This is done by turning the screws counterclockwise until the screws come out. Place all removed hardware in a bag for future use.
Install mattress onto wooden support system. There is no other assembly required as the support system is secured to the side panels of the crib.