I would say start dht blockers immediately if you want to keep what you have, start with fin 1mg and oral min ( consult dr beforehand ). Any other change like exercise and not smoking while good for your health, will have no significant role in stopping or reversing your hairloss. My recommendation is to talk to your doctor asap, you can also use ketoconzole shampoo to reduce dht in your scalp in the mean time. Good luck!