How to avoid premature ejaculation? -
Frequent masturbation and ejaculation stimulate acetylcholine/parasympathetic nervous functions excessively, resulting in the over production of sex hormones and neurotransmitters such as acetylcholine, dopamine and serotonin. Abundant and unusually amount of these hormones and neurotransmitters can cause the brain and adrenal glands to perform excessive dopamine-norepinephrine-epinephrine conversion and turn the brain and body functions to be extremely sympathetic. In other words, there is a big change of body chemistry when one excessively pratices masturbation. 
-www.herballove.com-
Note: Masturbation is a healthy sexual behavior. Like other behaviors, when over practiced or addicted it can lead to both psychological and physiological imbalances.  
The side effects of such changes to the body include: 
 Fatigue. Feeling tired all the time 
 Lower back pain 
 Stress / Anxiety 
 Thinning hair / Hair Loss 
 Soft / Weak Erection 
 Premature Ejaculation 
 Eye floaters or fuzzy vision  
 Groin / Testicular Pain 
 Pain or cramp in the pelvic cavity or/and tail bone
Did you mean, -pre-mature- or -immature- ejaculation?
Best to wait til your married.
Hopefully, by then, it will be neither!
if u masturbate you can slow it down
think of bea arthur
i also waiting for the answer. best luck!
Think about something nasty, like blood, guts, boogers, Roseanne Barr naked or just jerk off before you do the deed.