Don't dash then.
When you dash, you take the risk of tripping, the same way that GDubs takes the risk of swinging a 1 whenever he uses his hammer. It's controllable, if very annoying to work around.
As for my personal stance (because people are going to be drawing conclusions and stereotyping me from my previous comment), I don't give a **** about tripping. It barely affects the game negatively, so there's little incentive to remove it (beyond the fact that it's annoying as hell). On the other hand, it doesn't add anything to the game, so there's little incentive to actually keep it. It's such a complete non-issue to deal with, that it shouldn't matter if someone hacks their Wii to remove it or not.
That said, it's an absolutely terrible design flaw, and there's no reason that Sakurai should have put it in. It's not just a thorn in the competitive player's side; every single casual that I play with hates it. Generally, when you add random chance to something, the correct design choice is to make it all positive, or have the negatives and the positives balance out. In the case of D3's item throw, Peach's fsmash/turnip, etc., it's all positive. You always get something good to happen by using the move (except for GDub's 1, but that's offset by the 9). With tripping, it's triggered by a dash. Your opponent should not be able to kill you off a misfired dash, the benefits and costs don't add up to anything logical. There is no reason to make dashing any more of a tactical decision than it already is. Tripping is just bad game design, period. It was made to be hated.