Depends on how high of ABV it is, if its a standard IPA around 5-6%, leave it at room temperature(70ish) for a minimum of 2 weeks...then throw ONE bottle in the fridge for 24 hours and sample it.
If its not to your liking, wait another week and repeat...by week 4 it should be done unless its an imperial or other high ABV brew. Most of the time by week 2 its not quite done but still carbonated enough that its drinkable.
Putting it in the fridge is key, the liquid getting cold for several hours is what absorbs a lot of the CO2 into the beer.