I didn't say but she started the pawing when she saw me this morning. I always pop my head over the door and say hello before going and getting her rug. She was a little better tonight when I changed her rug.
Pawing in general is hard to eliminate because there can be some intrinsic reinforcement for her. Like it just feels good cause it's such a natural behaviour...pawing through the snow to grass, pawing at the water to splash cool water on their bellies etc.
But you can do it!! It just takes a bit of dedication and good observation. If you approach the barn and she starts pawing when she sees you, you can try two things. First, turn around and leave again...just for a few steps or until she stops pawing and then try and approach again. Second, and preferably, you can just stop in your tracks and freeze. IF she is pawing because she's happy to see you because you bring good things like food and attention etc, then she probably has associated that pawing makes you come closer. She paws, you approach, she's happy. Pawing worked! If you freeze when she paws, she will learn that pawing makes the vending machine stop!
So...you can only change that thinking by NOT approaching if she's pawing! It's tricky when they start pawing as soon as they hear the back door slam or the car pull up and we can't tell if they are pawing so it seems to them as if pawing is drawing you closer. The best we can do is try and notice is as soon as possible and STOP approaching (or even retreat - but I'd only try that second).
I also like to use my voice as a sort of bridge signal. So if I hear pawing I freeze. If the pawing stops I IMMEDIATELY start saying 'gooood' and start approaching. IF I hear the pawing I freeze again and my voice goes quiet. That way they have two clues - your body stops approaching and your voice goes quiet.
They can learn very quickly if we are able to be consistent. Is there anyone else who approaches her with feed or anything she values and if so, do you know if she paws for it? If so, it will be much harder to teach her not to paw unless you teach others how to handle it!
It's not really a matter of impatience...more of eagerness!
ANYTIME you are hanging out around the barn with her and she starts to paw, freeze or leave. You only need to leave for a few seconds. I would also say the words ugh ugh (or whatever you want) AS you are leaving so she can learn a 'no reward marker'.
Whatever you do, don't give her attention when she paws. The hardest thing I find is when they paw, I look at them!! And that's just what they wanted. So you have to train yourself when you hear the pawing, don't look up or move towards them - just leave.
You can also teach her to paw! That can be fun. She can solve math problems for you

They reason for doing that is to teach her the concept of pawing and NOT pawing. Like they teach barking dogs to bark on cue and then it's easier to teach them 'quiet'. So she could learn to paw when you asked for it and she could learn a cue for 'not pawing'. Like 'That'll do babe'

And then you just have to cue her not to paw when you see her do it 'off' cue.