1 day a week I will go for a long ride out and do tons of long trotting mixed with walk and canter.
2-3 days of flat work in the arena working on getting supple and responsive, working on compressing and extending the stride at all 3 gaits, tons of circles figures etc. (sometimes I throw in some poles)
1 day of jumping (I start small with just poles and low jumps until the horse is legged up a bit then start with courses and bigger jumps).
As my horse gets in shape I will add an extra day of jumping some weeks. I always give my horse at least 2 days a week off and I make sure they are not in a row, try and split them up so they don't get stiff after a couple days off in a row.
Good luck! I find the best thing for getting me in shape is getting a horse in shape!