Follow the direction on the label. Clean up, vacuum and even killed any large bugs. Sprayed bed an baseboards even around the floor. In 1 week had small ones back. Sprayed again will have to see what happens.
Second review on this product. It says to reapply every 4 weeks,but really need to do ever 3 weeks to keep up with them. It's about the best to use, have noticed fewer every time it applied.