After you realize you're stuck in a time loop, you should conduct some quick experiments to see how far it extends. See what happens if you don't get in to that elevator, or if you get in backwards and naked.
Double and triple check that you're stuck in a time loop before attempting such tests.
The point behind these experiments is to test the limits of the time loop, and see if there are any rules which might be taken advantage of. You may even get lucky and stumble on a way out during your experiments -- maybe the time loop doesn't want anything to do with you if you're the kind of person who would do such things to an animal.
Assuming that your time loop lasts long enough, you should be able to use your knowledge of the upcoming events to set yourself up nicely, at least within that current iteration. Win lotteries, buy stocks on margin or dominate your local underground horse fighting gambling den. With your new-found winnings, see if it's possible to buy your way out of the time loop -- rich people are always getting away with shit like that. At worst, you'll be able to suffer through your Sisyphean ordeal in nice clothes.
"You know something? I think causality is just jealous of us."
It's possible you're trapped in this time loop to prevent some injustice from happening, sort of like Quantum Leap with a less attractive protagonist.
It's always a good column when I can fit this picture in somewhere ...
So, look around for any injustices. An ugly kid getting picked on, or perhaps not getting picked on enough. Are people pirating Metallica mp3s still? That could be it. Also keep an eye out for any property developers. If television taught me anything, it's that property developers are always crooked, and always minutes from bulldozing a local youth center. By doing a rad skateboard jump over their limousine and beating them at their own game, you might just pull the wrench from time's cogs.
Some of our older readers might recall these things called compact discs, which were basically smaller versions of the laserdiscs we're all familiar with. When those things started skipping it was often simply because they were dusty or dirty. Rubbing the crud off or simply blowing on them was often enough to restore them to their former gloriousness.
My second favorite CD, after the Bloodsport soundtrack.
Apply the same principle to your local universe. Look around for things that are dirty and clean them. Mop up spills, pick up litter or bathe a homeless person. If that doesn't work, recall that physically scratched or damaged CDs could also sometime be repaired by polishing them with a mild abrasive, like common toothpaste. Look for things that are scratched or dirty and polish them vigorously with toothpaste.
"You touch me even once with that toothpaste and I will shoot you in the lung."