Depending on how much time you can spend in the area before you get there, here's what I would consider:
1. Don't do anything too rigorous for the first 24-48 hours you're out there.
2. After that, spend a day or two at a higher altitude doing some moderate activity - maybe go for a hike, or some easy workouts (you're tapering anyway, right?). "Climb high, sleep low". The rule of thumb is not more than 1,000 meters of gain per day.
3. Hydrate, hydrate, hydrate.
Really, I think this is kind of a strategy to lessen the effects - having 4 days or so in advance to get used to it will help, but never get you fully acclimated. The thing is that you're not at really high altitude where altitude sickness, AMS, etc. are a problem - you're just going to be dealing with reduced performance until your body adapts. You most likely won't have enough time for it to adapt, so it is going to be good to know your heart rate range, and race according to that. You might be tempted to try altitude drugs like Diamox, but I believe they can actually hurt your aerobic performance.
I've never heard of hypoxic training really working (at least for mountain climbing). It might get you used to the feeling of not getting air, but it doesn't simulate the other effects of being at altitude.
So, the resulting advice is just to spend more time at altitude if you can. There's no substitute for time.
Travis Rassat Vector Cycle Works
BikeFit Instructor | FMS | F.I.S.T. | IBFI Toughman Triathlon Series Ambassador