1. Mini flatiron. About $25 on Amazon. I let it heat up for 5 minutes while I am oiling my beard, checking for errant nose hairs or trying to find the dime that rolled off the counter under the cabinet. Anyway, this flatiron (used VERY carefully, so as no to burn you or char your moustache) is a wonder product. It brings all of the hairs to the same angle from whatever their natural growth patterns was. A pro-level variant on ironing is to compress the hairs (again, carefully) between the paddles and then turn my wrist to around 90 degrees so that the ends of the handlebar turn up and then gently pull the iron towards the tips, away from my nose. This puts a gentle curl to the hairs like scissors to ribbons, if you will. It is better to take many quick passes at your moustache than to try to pressure cook those hairs. I have done this scores of times without incident but it is possible to burn those hair right off if you forget you are flat-ironing your moustache and start watching a Breaking Bad marathon.
2. Too much / too little wax: Wax is sorta like fuel in an aircraft. Too much and it is too heavy and crashes. Too little and you run out and it crashes. The good news is, no one dies when you are figuring this out. I mean, that is really good news. If people died manicuring their handlebar, the liability policy I could have to take out would bankrupt me. Try altering quantities and journal the results. I am kidding about the journal. Actually, that would be interesting to read. So, journal. Then please share it. Include flowery language like they did back in the Civil War era too, please.
3. Moustache comb. Not "a comb I use on my moustache," but a bona fide (please note use of fancy Latin--that means I am serious) moustache comb. Preferably from Kent. Preferably purchased on CanYouHandlebar.com (link). Here is why: the teeth are super fine, so they separate the warring factions of the snake tongue into discrete hairs and coerce them into playing nicely with one another. Regular ol' black grandpa combs (of which I have owned dozens) were "ok" but no great shakes for wax distribution. Ideally, each hair should have a super thin coat of wax and should gently touch the hair next to it like a pack of youth group kids in inner-tubes going around the bend of a slow river.
4. Occasional trimming. When my handlebar gets super long, then my gravity defying feats begin to falter. This is not a recommendation, just something I have done on occasion

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