Learn from your stumbles . . .
I mean that, literally!
As you prepare for your first speech events of 2012 (which includes conference room meetings and client pitches, as well as those large-audience keynotes), and you practice your speeches or talking points (you do practice them, right?), make a note of any word pairs or phrases that you stumble over. If you can reword them so they are less awkward in your mouth, try that. But sometimes you can't rephrase your stumbling-block, because it is, say, a government project title, or the name of an important client. Then you need to say the words slowly and pick the phrase apart. Zero in on the particular combination of sounds that "bump up against" each other in a way that is awkward for your tongue or lips. Since these are muscles that can learn new tricks, all you need to do is practice the difficult phrase slowly, then speed it up till it rolls off your tongue. When you can say it five times fast, it can become one of your tongue-twisters for warm-ups.
If you don't already have a repertoire of simple word pairs to include in your daily warm-up, try these old standards. They are deceptively simple, but hard to do quickly and clearly, five times in a row:
toy boat
unique New York
You can find your own challenging phrases in real-life conversation. Here are a couple of my favorites:
tragedy strategy
shoulder surgery
Keep adding to your own collection, and practice your phrases at red lights. You can also practice while crossing the street, if you have your earbuds in or headphones on. No one will know.
Let clear articulation become a hallmark of your speaking in 2012. Aside from making you a stronger communicator, think of how much time you will save if you never have to repeat yourself!