Answer:
1) Exercise. Don't smoke or drink excessively.
2) Eat lots of fruits and vegetables. Almonds and walnuts are excellent because they help your body produce nitric oxide, which enhances blood flow to the penis.
3) Try a natural herbal supplement. Unfortunately, most use low-quality herbal ingredients in small doses. There are some, however, that are reputable and really can have an effect upon sexual performance.
Taking a top recommender herbal male enhancement supplement is the best way to go. They're design to reduce impotence symptoms.