Below my community link is the kind of posts you will see at Watcher's Defense Club .
I searched for the best practice and my wife and I find the fourth option best.
My wife and I have tried the first three videos and they don't really work for us. It's hard to get into those positions unless the attacker lets you do it. They all require a good strong core. Regardless, you should work on getting a good strong core; it will help in all situations.
Try them each yourself and see what works best for you. Then practice it regularly.