Amazing lesson with Beth - all kinds of things clicked!

I started my first clinic ride with Beth telling her that although I needed to keep working on all the things, I also felt like I was at the next step - a step that is so far out of my grasp that I don't even know what it is we'll be working on.
Beth told me.  :)  She said that it is beginning collection - getting Charlie to begin to step high underneath himself, and not go forward, but up.  And amazingly enough, that's what we started to do!
Beth was on fire with excellent descriptions of what was going on and how to adjust my body and what to feel, so it was just like:  Pow! Pow! Pow! with me "getting it".
We started with a walk (that marching walk that she doesn't call a march).  Tip #1:  If I lean a little more forward than I think is normal, the movement from Charlie switches from making me have a snaking back to hula hips.  Too far forward and I go back to snaking, but just a wee bit forward from normal, the movement goes left right left right in my legs and hips.  Once that happens, then I can squeeze/release (sometimes tap), and so long as I keep my hands firm so Charlie doesn't "leak out" the front, he starts rounding up and marching.  He is very good at getting me to open my fingers and let him stretch his neck out, though.
From a walk where I can halt or trot at any step - once it is at that walk but not while I'm still messing around with it - we can go to a trot.  Tip #2:  the crazy sashay I have in the posting trot?  Well, it is there in the sitting trot too.  I was in denial, but if I "tighten" my left side (easiest to do by putting my left elbow on my hip), *AND* let my right hip move (by thinking about it being equal with my left hip), then I quit sashaying so much.
Tip #3:  I can't feel it in my hips, but I can feel it in my legs.  So when I start trotting, if I check in on how each leg feels, I can even them out.  Generally, my left leg feels long and flappy (Beth says it kind of moves in a little circle but we'll fix that later) and my right leg is still all curled up tight like a tick.  If I think about making them feel symmetrical, then like a miracle, Charlie's shoulders balance up and he gets nice and fluffy to sit on.
We did some leg yields, and Beth says I am working too hard.  This was actually a theme throughout.  I give an aid every stride, so she made me lift my legs off and hold them off until I needed to give an aid again.  Especially to the right (off the left leg), I clench so tight I start lifting my heel.
An aid needs to have a beginning - middle - end, and most importantly, a purpose.  Charlie needs to react to it.  I can't get away much longer with my sloppy aids.  He was being bad today too, ignoring the trot aid the first time like he had no idea what I was asking for.
When I sat balanced and did a leg yield without lifting my heel, I could feel Charlie's whole body lift and move sideways instead of us just slouching sideways across the arena.
Charlie is a great horse to learn on because he makes you ask for it correctly, but once I do, he instantly rewards me by showing me how different it feels to do it the correct way.
Then we worked on canter.  Tip #4:  I need to close my knees and not let them flap on and off the saddle.  I'm not sure why (I was too busy concentrating on keeping them down to ask) but when I would rest them on the saddle, Charlie kept trying to use it as an excuse to trot.  Same thing with my aids too - I need to not ask every stride to keep him going.  He has to learn to keep himself going.
I also need to tuck my pelvis just a little, but that little bit helps me kind of root into his back.
Tip #5:  Then we worked on Charlie on a smaller circle at the canter.  This was pretty cool.  First, he would stick his neck up in the air, and my job was just to keep him on the smaller circle and not let him break.  Eventually, he would round his neck, and go from a hollow back hard to sit on horse to a round frame delightful to ride horse, and then we would make the circle bigger and then give him a break.  It was much more difficult for both of us to do going to the right.  His weak left hind leg, my crookedness.  (Although!  Tip #6:  if I turned just a tiny bit to the outside, I suddenly got balanced and everything got easier - it was a "eureka" feeling for what is happening with the sashay at the trot)  Anyway, what happens is he is figuring out that he can step under himself with his hind legs instead of shooting them out behind him (like that lesson with Asia), and when he tucks them under, he automatically gets round and soft in his back.
All in all, it was an amazing lesson.  Beth showed me exactly what I needed to start looking for and how to get it and how it felt.
There are probably a zillion other tips that were in the 45 minutes, but this feels like enough to work on for the next couple months!