By doing what he always does, being creative with his own abilities. Anyway, as we have seen time and time again Blackbeard is not undefeatable. If Whitebeard wasn't in such a bad state at Marineford he would've won and Blackbeard still needed his whole crew to attack Whitebeard before he was dead and you can argue Whitebeard was the strongest man but at Marinoford he was definitely not in his prime anymore and while fighting BB, He already had half his face blown off and was magmafisted in the chest by Akainu. MAgellan also basically killed BB if it wasn't for Shiliew having an antidote so there's definitely ways to defeat him. True, he is hax but I think Luffy will have something to even the match. Rubber and quakes? Rubber absorbs quakes. I don't think Luffy will be affected by these quakes at all or at least much less then any other human would.
Against Croc he used water to counter his ability, against Enel he was the counter himself, Lucci was a simple who can be faster and stronger, Moria he used Morias actual abilities, Magellan he used someone else´s abilities to be able to even touch him, Hody was much weaker, same as Caesar, Doflamingo he needed Law´s super hax ability, and the help of an entire army of gladiators. Not quite his "own abilities".
BB´s overconfidence will be his downfall definitely, but the two opposites are pretty clear, while Blackbeard always takes the easier route while willing to risk it not working out to acquire the supposedly best abilities, pretty much putting his path in destiny´s hands (hence why they refer to it so often, he would have given up if he had never seen the darkness fruit, the BB Pirates would have disbanded if he failed to steal WB´s fruit), Luffy is getting in there every chance he gets and takes his destiny into his own hands to acquire what can be considered "real strength", which also has been mentioned from the beginning of the manga, with the contrast of Luffy´s one spear of conviction and determination vs external abilities and strength, and that literally ties into Haki and what it means.
You seem to forget BB has an ability to completely negate Luffy´s ability, and you can bet your ass it won´t stay as simply pulling him into his hands and touching him that way, with the concept of Awakening, BB can negate Luffy´s powers from anywhere.