i managed to get mine by 41 without doing any bit of mob farming or AH playing, i literally just quested and vendored everything useless, didn't use gathering professions for selling either. could've easily gotten it by 40 if i used gathering professions or didn't over-level my blacksmithing for my current level.
as has pretty much already been said, the only things you can really do is to train as few skills as you possibly can (i trained maybe ~5 skills from 30-40) and put your profession leveling on hold when you reach lvl ~30-35. you're already 36 so it may be too late to get it at exactly 40, but even if you don't get it by then, i'd still recommend that you just continue questing and get your mind off the mount until you reach 100g. the quests and mobs at 40 give such good rewards that grinding for the mount seems pointless.