I actually used a tint bottle, like they use in salons to color hair. I did cut the tip so the hole was bigger. Home Depot sells DE as a pesticide. Made by Safer. You must take apart your bed to treat it. If your framing is hollow make sure you squirt some in there. Take apart all furniture and cushions and get it inside. Clothing drawers and towels all should be washed and dried above 120 °F. Good luck! I did all that.  And used a steamer and professional pesticide and I'm almost 7 days in and I still have them. Hope the DE works.