They are very sneaky because it is not easy to see them. If you happen to find a single bed bug in a particular room, you should be on high alert because there is a possibility that there are more of them in the house. They will wonder around the whole house breeding, therefore you should be ware of other rooms in the house.
Bed bugs have a really bad smell.
You will easily tell the difference in pattern of bed bug bites from those of other insects like mosquitos. Some people will have irritating itchiness that will not stop and thus you will know that the bites are caused by bed bugs.
It might not always mean that a bed bug bit you, the stains might be human blood.
You should look for bed bug fecal matter in your bed sheet and your mattress.
You will not be necessarily looking for the bed bug eggs. The eggs are one millimeter long and are pearl white in color. So, if you come across be bug eggs in a particular bed in your house, you have to check other rooms for the same more.
Bed bug skin castings are also an identification of presence of bed bugs in your home. For you differentiate between the bed bug skin from other insects which might have the same features, you will want to look for a hollow translucent skin underneath of your mattress.