Artemis BJJ (MYGYM Bristol), Can Sönmez, Bristol, UK - 10/08/2015
From half guard, get in as low as possible, curling in towards their leg like you do for the toe grab sweep. Sometimes they keep their foot out of range, which is when I like to try for a position called deep half guard. Shoot your non-underhook hand between their legs, reaching for their opposite bum cheek. The key thing here is to get your shoulder underneath, rather than trying to wrap their leg with your arm. You want to wriggle underneath as you swivel onto your back, your head on their thigh.
At the same time, drag their leg towards you, using the leg you have on top. Your aim is to get your entire body underneath their leg, accomplished by your swivelling motion. You may need to push off their hip with your other hand, to help that wriggle underneath them. Once you've swivelled, reach your first hand around the outside of their leg, gripping the inside of their knee. You other hand tucks underneath their leg, so they can't grab it.
Finally, your legs are trapping their one leg. Make sure at least one of your legs is hooked over the top, so they can't just remove their leg and pass. Your other leg could be locking your other, or some people prefer to hook under their opponent's leg, meaning they can lift.
Teaching Notes: I had been intending to show the entry then progress to the Homer sweep, but almost everybody was having trouble getting the concept of swivelling underneath. That was compounded by the people on top not being familiar with the position either, so they were sometimes just falling over. Now, that would be great in sparring, as you'd have the sweep, but it makes it tough to drill deep half.
Next time, I'll leave this until later in the month, when people should hopefully be more familiar with balance in half guard and have played with the toe grab sweep a fair bit. I'll be emphasising scooting underneath, which leg you're reaching under and the possibility of using a push on their hip to help your wriggle. Tweaking the leg out like Jason Scully might make it easier too.
On the plus side, there were a few people who got it, including Milka. That made me happy, as she's still quite new, so my instruction can't have been totally unclear. ;)