TenaciTea said:

Do you have access to a small arena, large stall, or a round pen? You could try free lunging her, and giving her something interesting to do, like go over a pole or small jump

Shingashina said:

If she wants to go fast and not listen, make her bored. I have a barrel horse that wants to be all gas and no breaks, which is usually what I ask for to be fair, but if I want her to slow down and start really listening to learn something new, I'll pick a place in the pasture and just start trotting circles. I use both hands on the reins for as long as I need to show her where the circle is, then we I loosen up the reins and trot circles for as long as it takes for her to relax. I know she's relaxed when I can switch directions without contact on the bit and stop with minimal contact. By that time, she's doing a slow, smooth trot because she knows that she isn't really going anywhere and going fast isn't going to change anything. Then, we can work on whatever slow thing I want to work on with it. It's just a matter of letting her know that there's no reason to go fast and that she can have her head and relax. Works wonders for her.

Heaven on Earth said:

My friend has a trainer she uses on her horses that I am considering having come out and see if he has any tips or ideas.