what do you mean by "bluffing high"?
i find, when it comes to bluffing, most people fail because they've not told a convincing enough story. there's also a tendency for a lot of people when they've fired two shots, to over-bluff at the end when it can just look like you are trying to buy yourself out of a bluff gone wrong. you also have to play the player you're up against and consider their range and what their bets are telling you.
your own table rep. is important too - if you get a couple of bluffs called down and lose, people will remember those hands so if you're using the same gear every time, you're going to get called every time.
can you walk us through a hand where you lost?
alasdair