As far as I know, order doesn't matter. It does matter though the max pressure AND the difference of pressures between the chambers. As you may know the chambers are seperated by diafragms, which would bend towards the less presurised chamber. So inflate the first chamber a little less than the optimum pressure you want to achive, then the next one to it, having in mind that at the end of this procedure you must have the same pressure (if possible) to all of the chambers.
Michael a.k.a "Bat Falcon"