There are certainly signs a
cheater would not think to cover up; in fact you'll find many more signs of cheating often overlooked but the unfaithful spouse. I am about to discuss one of these
signs that just may give you the answers you are looking for.
Cheating Wiki – Below is an excerpt from Wikipedia in which it suggests that you look up Adultery.
(also called philandery or cheating, anglicized from Latin adulterium)
is sexual infidelity to one's spouse, and is a form of extramarital sex.
Cheating takes place in relationships and marriages, with the latter usually carry more serious consequences when it is discovered.
However in order to discover the dirty little deeds that your partner may be carrying out behind your back, you have to know where to begin looking. While the cheater is cheating, they are simultaneously thinking of ways to cover their tracks. So you have an uphill battle from the start.
However, if you know the signs a cheater often leaves behind then you have one up on them.
Before I go further, let me refer back to Wikipedia and add to my
Cheating Wiki. When you look up “cell phone” on Wikipedia, you will
find the below excerpt. So in something as general as cell phone, the
mention of cheating and infidelity is present. Take a look.
A study by Motorola found that one in ten cell phone subscribers have a second phone that often is kept secret from other family members. These phones may be used to engage in activities including extramarital affairs or clandestine business dealings. 
Okay, so you probably realize that the sign of cheating often overlooked that I am about to mention has to do with the cheater’s cell phone.
After a long session of cheating with their lover or even a loose night out with their friends, the initial period when they get back into the house will be the most important time period when trying to catch your spouse or partner cheating.
Tip#1 – This is especially true after a night out of drinking, but the cell phone (especially the new smart phones) has too many aspects for the cheater to cover up initially. You have social sites like Facebook attached to the phone, and often times the cheater will leave the phone logged in so accessing his last post and in box messages will be easing pickings. He may remember to delete the calls received, but do quick searches on the messages sent, or check the draft messages.
Did you know the iPhone has a feature on the home screen to search the entire phone? How about trying a quick search for the term “pic”, “muah”, or even “miss you”? Get creative, search for the term “baby” or “honey”.
will return all the mentions of these words, including emails, pictures,
text messages and anything else on their phone. There are simply too
many places for the cheater to cover up, all the time.
Tip# 2 – Once again, the smart phones are very smart. Do realize that when you open your text message or phone book, it goes to the last person that you sent a message to or called? Checking this feature at random but focused times.
Why did the name of a co-worker show up after
a late night out? It may be legitimate, or not! Testing this tip could
point you in the direction that you may or may not be ready to go.
The above are just a few signs a cheater would not think to cover up, and there are many more. Please come back as I add many more often overlooked signs of infidelity and cheating.