The pat: Some men lean in with their left arm around your shoulder while their right pats your upper back three times. Too many pats could mean he's signaling you for some foreplay. Too few means he'd rather be hugging his sister. As opposed to the full body hug, all lower man parts stay a respectful foot away, possibly to hide an awkward boner. In either case, if he gives you the shoulder pat, his performance in bed is probably just as tame.
The full body: This hug, involving the body touching from chest to knee, is a clear sign of genuine affection. Typically this isn't left for a quick hello or good-bye hug, but when some type of feelings (love, lust, or like) are involved. Whether you want it or not, anticipate more body contact from this person in the near future.
The side hug: This maneuver is reserved for those who are uncomfortable with their situation. These guys aren't sure if they should give the polite, quick hug/pat, pat, pat, or a potentially uncomfortable full body hug. These are the same guys who'd also prefer to have sex through a sheet or without any direct eye contact.
The man stare: Some men like to look you straight in the eyes. This is often a sign of a man attempting to claim superiority. He won't look away, wanting you to feel uncomfortable and glance away first. This behavior may have its roots in psychology. The inability to look into someone's eyes is a sign of dishonesty. To create an image of straightforwardness and confidence, men will purposefully stare into your eyes. Also, subconsciously the mind is able to detect slight variations in pupils. The more dilated a person's pupils are when looking into your eyes, the more likely they are attracted to you. If he's attracted to you or wants to get your attention, a man will stare at you intently, hoping for a reaction.
Emails: An email from a man who has no professional connection with you is often a scripted sign of interest. It means he has taken some time to tell you what's on his mind, and has arrange the verbiage in a manner to garner your attention. If the email is sloppy or short, either a). he's drunk and just trying to work on a potential booty-call he doesn't really care about, b) he's lacking in mental capacity, or c) he's not interested in you romantically.
Text messages: Texts are a quick way for men to get your attention and feel you out without the awkwardness and commitment of an actual call. The intelligence of their quips and one-liners either shows you how much they're into you, taking time to charm you electronically, or how versed they are at flirting via text. Hopefully you can see these messages for what they are: lame pickup attempts by guys who can't even commit to calling you.
Instant messages: These are another means for a man to get your attention without actually having the balls to talk to you. If only relationships were conducted online, these guys would be the perfect boyfriends.
Status updates: At the beginning of a relationship, it's common for both parties to do some light cyber-stalking. Some men may announce to the world how they just had the best afternoon, hoping that you'll see this and think that he he's a closet romantic. No. He's just trying to be sneaking about getting laid. For other men, status updates are a lame attempt to help you stalk them in person. If he's suddenly "drinking coffee at Starbucks," then "going out for a night at the club," he's too chicken shit or noncommittal to invite you out directly.