Guide for teens to maximise penis size. (It may help older males too.)

Tips to increase penis size:
You should do the following from the ages of 14 to 21. (It may help older males too - worth a try)

1.Stay lean, thin and muscular with exercise such as running and weights.
2.Eat well.
3.Don't masturbate too much, and when you do, don't damage penis by applying too much pressure

Exercise increases testosterone, the male hormone.  Weights are especially good for this.
Being thin means less cholesterol (the fatty stuff that clogs blood vessels), consequently testosterone is more effective.
Being thin also means there is more blood flow to the penis; so when you get spontaneous erections it stretches out the 3 spongy chambers of the penis.  See diagram: http://en.academic.ru/dic.nsf/enwiki/265769o
Don't masturbate too much as this depletes energy and effects hormone levels.  The penis was not designed for the strong pressure of the hand.  Over-masturbation is likely to damage the delicate spongy chambers of the penis.  This leads to energy being diverted into repairing the penis rather than growth.
I would avoid spending time on the computer as this resists the temptation to look at porn and masturbate.  Also the electro-magnetic radiation from the monitor is not good for you if your head/brain is too close to it.
You should be getting spontaneous erections.  Erections are good for expanding out the penis with blood.  This happens a lot during sleep.
So be thin, muscular and don't masturbate too much.
Other masculine traits will result from this too: deep voice, wide angular jaw and pronounced chin, pronounced forehead and big space between eyes.

If you look on the subreddit massive cock you will notice nearly all are very skinny: https://www.reddit.com/r/MassiveCock/

Why jelqing is bad:

The concept of “jelqing,” if not the actual term, has been around for as long as men have felt insecure about the size of their penises…which is to say, a very long time. (Some proponents claim it stems from ancient Arabic texts, though this is unconfirmed.) Put simply, jelqing entails stretching out, or “milking,” the semi-erect organ for a set amount of time per day, which theoretically creates small tears in the penile issue, forcing the growth of new cells and thus a small increase in size. (Others have suggested that jelqing enlarges the blood chambers of the penis, creating more blood flow to the penis and thus larger erections.)

Of course, there’s very little actual research suggesting that this is true, says Yaniv Larish, MD  partner at Fifth Avenue Urology in Manhattan. In fact, when patients have approached him asking if they should try jelquing, “I routinely advise patients not to perform it,” he told Rolling Stone.

“And the reason is because when you do that stretching technique, essentially what you’re causing is a microvascular injury to the erectile bodies of the penis, the corpus cavernosa,” the chambers in the penis that fill with blood when you get an erection.

https://www.rollingstone.com/culture/culture-features/jelqing-penis-size-increase-length-841045/