You can just stop looking at the porn until it wilts, or you can actively think of something else. A combination of both works. It doesn't need to be unpleasant - just think about groceries, or even about girly things if you want, just nothing sexy.
You'll still get morning wood because that's a physiological response, but the moment you're awake enough to notice your erection, it will wilt. (It's actually useful in diagnosing impotence - if a man still gets morning wood, it points to a psychological issue rather than a 'hardware' problem.)
This is one of the mindfuckier elements of the process, and also helps keep you limped once you succeed. It's a nice weekend, you wake up horny, dude-brain kicks in and you go to grab your dick...but you don't have a dick anymore, it's a clit now, so by the time your hand closes around it, it's gotten nice and small and soft. One of your hands absentmindedly strokes one of your nipples, and it feels good, so you start pinching and twisting it, and you realize you're doing that automatically now, and the message gets driven deeper: you have a clit now, not a dick.
Your masculine ego flares up a bit, and you start trying to get hard - really trying this time, but you're not only soft in your hand, but rubbing your shaft feels boring compared to that pleasure from your nipples, and you realize that now your asshole's awake too, and it's feeling empty. Maybe at this point you give up and reach for your dildo and take it for a ride, and your inner male dies a little bit more? Or maybe you're feeling a bit more defiant this morning? You spend the next 20 or 30 minutes teasing yourself to a pathetic half-mast that quickly shrivels up to a small nub that just barely qualifies as plumped with a bit of blood. You've already wasted 20-30 minutes though, so you sigh and fumble around until you realize that if you grip the head between two fingers and rub in little circular motions to match the pace of your nipples, it feels really, really good. And it's in that state you cum, and you realize as your horniness fades that you just stimulated your clit, and your masculine ego dies a little.