The best ways to make the penis bigger naturally are to lose weight in the groin area and for men to do Kegel exercises. “There is almost as much penis inside the body (as an anchor) as there is visibly outside of the body. When a man loses weight, the exterior portion will actually be longer. I believe it is about 1/2"-1" for every 10 lbs lost. It is why often skinny guys seem to be more well-endowed,” says Yelverton. Kegel exercises strengthen the pelvic floor and the majority of men in studies report longer and stronger erections (which men often equate to size).
Again, holding the glans, pull your penis away from your body. Then place the thumb of your other hand on your shaft, at the base of your penis, and press down with your thumb while lifting up with your other hand. Hold for a 10 count. Repeat this exercise to the right and to the left, placing your thumb on alternate sides of your penis in order to create tension. Continue stretching — alternating among up, right and left, but never down — for five minutes. Repeat once or twice per day.
Eat watermelon. It's not an herb, but it has properties that might help increase the size and duration of erections in a similar way arginine. Watermelon contains an amino acid called citrulline, which gets converted into arginine and leads to the dilation of blood vessels. The fact that watermelon contains citrulline is a relatively new finding, so no studies have been conducted to find out how well it really works or how much watermelon you'd have to eat to see the benefits. However, since watermelon is considered a superfood when it comes to men's health, you can't go wrong by eating plenty of it while it's in season.
Update 10/20/2019: A new metastudy done by scietists from Italy and the UK reviewed several non-surgical and surgical approaches to increase penis size and evaluated their risks. The results are fully in line with out own and support the statement that penis surgery and almost all of the devices and pums sold for enlargement present a high risk and very limited results.
The side effects of lengthening surgeries are numerous and include infections, nerve damage, reduced sensitivity, and difficulty getting an erection. Perhaps most disturbing, scarring can leave you with a penis that's shorter than what you started with. Widening the penis is even more controversial. Side effects can be unsightly -- a lumpy, bumpy, uneven penis.