Generally if you feel them pulling away while on their knees, simply keep the pressure of your rubber guard at your knee while also leg curling over their back with your second leg. If your problem is when they stand up, this wont usually work as they have a lot more power on their feet, in this case, hook their leg so they cant pick you up and slide your second leg up to get a full dead orchard. Eddie made an MTS called "rubber guard: the standing battle" in which i think you can benefit from.