Remove all the bedding from the mattress and place it in a plastic bag. Vacuum the seams, labels and other areas of the mattress. This will get rid of dust and other debris.
Add some warm water to the steam cleaner's water receptacle. Check the manufacturer's instructions for the correct amount. Hold the nozzle directly to the mattress, to increase the effectiveness of the steam.
Move the nozzle slowly along the mattress. Pay special attention to the seams, under handles and around any labels. Continue to steam the mattress until you have completely steamed all the affected areas. Also do the headboard, box spring and bed frame.
Leave the areas of the mattress that were steamed cleaned to air dry thoroughly. To ensure that all the bed bugs are eliminated, you may spray the mattress with a bed bug spray.
Enclose your mattress in a zippered cover, to help to prevent further infestation.