I didnt read all the replies, so you may have already had this answer but i hope i can help anyway.

1) try sitting as quietly as you can. Just relax all your muscles so you move with the horse and stay in your seat.

2) TRY to stay calm!

3) try to engage right side of horses brain. Ask for circles, changes of rein, if you can next time- transactions. Get him/her thinking rather than acting on instinct

4) RELAX YOUR LEAGS AND SEAT! Getting nervous automatically makes you tense your bum and legs so think about them and make an effort to relax them.

5) shove your heels down as far as they can go and move your legs a little further forward than you would have them normally. It will stop you from being thrown forward.

and of course, once a fall- get straight back on!

Good luck

__________________
* vegan hippie girl <3

Have
female Royal python
male Bengal cat
7 Golden Spiny Mice

Want
indian stick insects

I had my confidence knocked when I was riding an extremly spooky horse who would jump at her shadow, I was realy enjoying riding her until I came round the corner at the top of the school and there were a bunch of kids in the seating area the sudenly dicided it would be a good idea to stomp out of the schools seating area making loads of noise, well of course she swerwerd and I went out the side door. the next time I rode her I had it recomended that I should have a leader, to help me regain my confidence in her and get used to her and how to relax her if she dose spook, i havent had a leader since 2008 and that happened last year, maby this could help.
if it dosent ,all horses are differant this is just what helped me