I'm leasing a quarter horse mare named Candy, she will be 4 next month. Recently I have been working her on the bit. She has the correct head set but I realise flexing at the poll should be the last action when a horse comes 'onto the bit'. I feel like she's stiff and not lifting her back or engaging her hind. I try to acheive more impulsion but I feel like she just rushes forward.
How do I achieve impulsion and allow her to step under herself and lift her back?