Watch the instructional DVD that came with your machine and refer to it often when trying a new excercise or to ensure you are doing your "routine" resistance training correctly. One way to do this might be to put a specific video chapter up for an audio/video walk-thru to accompany sets you are doing until you refine efforts.
Not sure which model you have but I have a Bowflex Xtreme 2 SE. If the following are possible on your particular machine, consider trying the excercises listed below on for size...maybe in sets of 4 with 12-15 reps with low-to-moderate resistance for starters; after acclimating perhaps frequency would be 4 times a week with a day of rest between (of course you should adjust frequency & resistance to your condition of health and requirements):
First and Third Workouts of Week:
Triceps/Hammer Triceps Extension
Second and Fourth Workouts of Week:
Lat Pull Downs
Decline Chest Press/Incline Chest Press (alternate these and/or mix them up)
After a while, excercises like the ones listed above can become sort of a foundation for you to customize specific routines you establish, all the while planning to alternate and mix-up sets occasionally with all the available resistance training movements that you guide yourself through and/or reacquaint yourself with via the instructional DVD, etc.