Good pointers!
Equipment:
Gloves
stud chain
lead rope at least standard length, if not longer.
I would add, don’t let the lead get too long, keep his shoulder at your shoulder (NONE of that parelli long lead, horse trailing behind you stuff!!).
If he starts to turn his head away from you and drag…you need to INSTANTLY react!
I would use my voice, loudly to get his attention as I:
Grabbed FIRMLY on the lead, dug my heels into the dirt, and YANKED his head around. No nicey nice here, this is LISTEN TO ME NOOOOOOOW stuff.
Things that might help turning the big ol’ guy as he takes off… Digging an elbow into his shoulder / neck attachment along with the yank and growl to help get his head turned. (also, on the same note, there is a pressure point where the lower neck muscle meets the chest. You can grab this point, and it will immobilize or slow down most horses, and cause them to flex their neck, and turn their face towards you.)
If the above (yell, yank, elbow / neck pinch) does not work, I would probably whorl the slack of my lead rope and give the hind quarters a good whack on the right side (along with yell and yank ) to disengage the hind quarters, hopefully spinning the horse around to face me.
When you get him under control, I would ask for a bit more (ie backing, or otherwise submitting) and then praise. Use your voice while training through this. If you are consistent (voice, yank/ shank, backing), he will start to anticipate the punishment when he hears you reprimand him (use the same thing each time, like a loud "HEY!). I have one or two like this that have been reformed. Now and then they will turn like they are going to take me for a drag, and all I have to do is yell HEY! While raising my hand (to yank on the lead), and they stop in their tracks.
I am usually not a yell, scream, growl, yank and shank kind of trainer, but there are some things you need to get their attention, “running off” biting and kicking get this sort of reaction from me. They are all REALLY dangerous things for horse and handler.