I posted this in a Mastermind I'm part of sometime ago. I guess it's useful here too. --
Let's say a friend comes to you and say: "Dude, there's this new restaurant in town, pretty sweet, you should check it out." Ok, cut. Flash forward. You visit the restaurant and it's the most awesome-cool-amazing thing that you are aware of in the past century. Nice, huh?
Another friend comes to you and say: "Hey, just found the most coolawesome theater that I've ever seen! It's comfortable, full of nice people, etc etc. Man, you must check it out, like, today. Are you going today? No? Go tomorrow. Please, you need to see that". Cut, flash forward. You visit the theather and it's just a slightly cool theather.
Hmm... there's a problem here.
I don't have a well-defined theory to explain why this happens, but I got some ideas. In general, people try so hard to turn everything into an awesome thing, like, they can't living in a regular world, that it's too damn common the use of hyperbolis. And that's bad, because it messes up the communication: the listener will never take you serious.
Another way this comes up is in the internet. Your friend posts something slightly funny, you like it and comment "hahaha". Another friend posts something still funnier and you like and comment :"hahahahahahhah". And so on. In the end, to express that you're laughing hard at something, you're gonna need a hell of a string of haha's.
But, the problem is not just in talking and writing: body language counts too. If you usually moves too much, never stops your arms and legs, your movements will be automatically less meaningful for people around you. The same thing for facial expressions.
How to correct this
I noticed all this while reading hpmor. All characters expressions are meaningful: maybe because some of them received training in how to manipulate people? That's why I'm interested in mirroring Draco's modus operandi (if you haven't read hpmor yet, make yourself a favor).
- Talk less, more slowly and, when you can (and it isn't awkard), make some pauses  in your speech (btw, this helps with your second language, in case you're using one)
- Move your body less; try to communicate single points (like yeah, nay, etc) with your face. If possible, search for facial expressions images and practice in front of a mirror.
- Recalibrate the scale of your adjectives. Not everything is awesome or horrible: on one hand, it can be fine, sweet, cool, interesting, good, really cool etc, and in the other hand: not good, bad, unpleasureble etc. 
 Quoting directly from "Language Hacking Guide"
"For example, if I need a moment to recall the way to say a key word, I could say "I'm going to the..." [raise index finger analytically, take a step back, breath in deeply as if you are about to reveal the secret of life the universe and everything, and look out the window at the quest that awaits you] "... supermarket! Do you need anything?"
Don't overdo it, though.
 As native english speakers (I suppose). you can come up with better examples here than I.