I see quite a few people suggesting a limping strategy, limping with weak hands and raising with strong ones for instance. I'm sorry, but that sounds a little fishy to me. That is to say that's how fish tend to play.
My first thought is that it won't take very long for anyone paying attention to pick up on it. Secondly, when you start limping in with spec hands with the rest of the limpers, you are just playing bingo. In all likelihood, you're going to find yourself bleeding chips. Every time you flop bottom pair or some kind of draw, even a backdoor draw, you're going to feel compelled to continue in the hand and chase your draw. More often then not, you won't get there. And when you do, you'll just be replacing the chips that you lost on the hands when you didn't. In truth, that's pretty much what happens even when you concentrate on playing quality hands. The difference is that when you limp in, you will be doing it against half of the table, which is going to lessen your chances of winning the pot. But when you play higher quality hands, you end up playing less hands and throwing away less chips in the meantime.
Not only that, but playing limped pots with half the table makes it hard to play post flop. It's difficult enough, trying to put a single player on hand. It's exponentially harder to put three or four players on hands. So you're always going to be second guessing whether or not someone is ahead of you. After all, with so many players in the hand, somebody had to flop something, right?
But the question was what to do about the limpers, not whether or not you should join them. I definitely say not to join them. All I can tell you is what has always worked for me. And that's playing tight/aggressive poker, raising 3x + 1x for each limper in front of me. I might not try for the full double up every time I think I'm ahead, but betting two thirds of the pot on three streets tends to build a decent sized pot and take a healthy bite out of a players starting stack. Once I've gone to showdown once or twice and other players see that I'm not raising light or
bluffing, then I will start mixing my game up. I'll start switching up between leading out and check/raising and trapping and trying to induce bluffs. As my raises start getting more respect, I'll start opening my range. One thing I make sure to do is to play every hand in my range the same, whether it's A-A or Q-8. If I think my opponents are starting to get comfortable calling me, I might tighten my range up for a little while.
That's what has always worked for me. In fact, it's worked so well that nowadays I often find that my raises get respect from the moment that I come to a table. I attribute this to more and more players utilizing HUDs so that they can see right away my VPIP, PFR and win rate and know right off the bat that they should be respecting my raises. As a matter of fact, it kind of sucks because I find it harder to get action then I used to.