I assume that you are under a physician’s care.
Things usually recommended are trying to lose weight if applicable and engaging in regular aerobic activity. There are also dietary recommendation called the DASH diet, and here is a link with more information http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/new_dash.pdf. This information is issued by the US Department of Health and Human Services.
I wish you good health.