It's confusing, they call it 'yielding the hind end' when the front is still and the back is moving, but it's called a 'turn on the forhand' when the same thing is happening, so it gets confusing.
I like 'yielding the hind end' because it's more literal.
To get them to yield the front end, if you watch the video of the girl with Pink you'll see her apply pressure to the horse's shoulder, the squishy part. The appropriate response is for the hind feet to stay still and the front feet to cross over. This is probably the hardest skill for horses to do - so be patient with this one, but this is a great respect building skill. If you find the horse backs up when you do it you're pushing too far forward, if they walk forward you're pushing too far back, applying a little pressure to the lead to help stop forward motion is helpful too to guide them. Just make sure you give slack when they try to turn away from you. You don't want to bump their head if they're doing the right thing :P
You can also teach them to side step, by pressing just where your foot would go on their side when riding - this you want them to step directly sideways.
Good luck, keep up the good work