First of all remove all myths & misconceptions from your mind about masturbation
In fact, Masturbation is completely normal & doesn't have any bad effect to the body and mind.
Health can be improved by having a balanced diet rich in fruits, vegetables, fish, nuts & honey.
..this helps in improving concentration, memory & builds up the confidence level.
Maintain adequate hygeine to prevent genital & urinary infection.
One more thing...avoid consuming any over the counter medication
which claim to increase the size of penis or improve performance...it may be harmful.
Best thing is to eat a healthy diet, exercise regularly, avoid stress, get good sleep, think positive and stay happy.
Wishing you a Healthy Life.