Here's my first experience. Great orgasm first time I masturbated! Still going strong, thousands of orgasms later!
When I was younger, I found a blue book on my bed called Boys & Sex. This was probably from one of my parents, meant to educate myself on sex.
Well it really covered every aspect of sex and had a few illustrations, too. I was noticing changes in my body, especially frequent erections so this helped explain things. So one day I was reading the section on masturbation while sitting on the toilet and was getting very horny. My cock was very hard and standing straight up. I wrapped my hand around the shaft and started pumping it up and down slowly at first, then faster as the pleasurable sensations increased.
It was starting to feel so good and I was breathing hard and thought I was going to burst! Soon my white cum started spurting out in gobs all over my hands and belly. I was so excited and just felt ecstatic. I couldn't believe how great this felt and it was only the beginning of a lifetime of exciting solo sex!