Hello dear..
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.
Secondly, the size of penis is genetically determined & cannot increase after a certain limit.
However...performance can be improved by having a diet rich in fruits, vegetables, fish, nuts & honey.
Avoid
smoking & alcohol.
You can also do oil
massage of the penis...it increases blood flow & maintains the erection.
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.
Take care.