According to an article on the American Academy of Dermatology website, to look for bedbugs, check for these signs in the places where people sleep.
• A sweet, musty odor: Take a deep breath. If you notice a sweet, musty in the room, there may be a heavy bedbug infestation. Bedbugs produce chemicals to help them communicate.
• Specks of blood on bedding, mattresses, or upholstered furniture such as couches and headboards: Look carefully at blankets, sheets and mattress pads and then check the mattress and box spring.
• Exoskeletons: Bedbugs have an outer shell that they shed and leave behind on the mattress, mattress pad or beneath couch cushions.
• Tiny, blackish specks: Blackish specks on the bedding, mattress, headboard or beneath couch cushions could be bedbug excrement.
Eggs: After mating, female bedbugs lay white, oval eggs in cracks and crevices. These will be small, as a bedbug is only about the size of an apple seed.