Adult bed bugs are small, about the size of a pinhead, and are pale to dark brown. They often hide in cracks and seams, so look closely at your mattress, and your box spring by shining a torch into any dark crevices. Bed bug eggs are even harder to see, as they are white or transparent and tiny. They are similar to head lice eggs but will attach to the fabric of your mattress or other soft furnishings. Often the evidence that's easiest to spot is fecal stains. These look like dark brown or black spots and can sometimes be mistaken for mold. Bed bug feces is almost entirely blood, so even though it will dry to dark brown, if rubbed with a wet cloth, it will turn red. If you find these clues, it's best to call in an expert to assess the size of your problem!