Walking, running, swimming, biking, and rowing are all good choices. Varying the kind of exercise you do may help you stick to it. Avoid exercising in extremely hot or in extremely cold weather. Keep your blood pressure down. If you have hypertension, it's very important to keep it under control.
Regular exercise is one way to help.
Your doctor may also prescribe an antihypertensive medication for you. In addition, low-salt diets are generally helpful. If any kind of medication is prescribed for you, take it exactly as instructed. Your doctor has determined the type and amount of medication you need. Follow the instructions carefully and raise any questions you may have with your doctor.