In general, we recommend "non-pharmacological" therapy ie the things that you can do, without a prescription. (If one develops a fracture, medical therapy may be indicated.) These are the same recommendations that are given for general bone health:
1) Calcium: 1000-1500mg per day, in divided doses, from all sources (supplement and dietary consumption).
2) Vitamin D: 600-1000 units per day.
3) Weight-bearing exercises.
4) Strength-training exercises.
(Please see other posts for ideas regarding weight-bearing and strength-training exercises.)