All by myself, when I was really, really young, we are talking about early elementary school aged. It tickled and I liked it. I did not cum of course because you cannot cum that early on in life, but I liked the fact that rubbing it through my underwear or pants tickled me. I had no idea what it was, but I thought it was fun, so I proudly showcased it right in front of my parents, not naked, but just rubbing it through my pants that day through the couch. They were shocked to say the least, no idea where I learned it from, and told me not to do it again without any explanation. As the years went on, and as I was going entering into puberty when I could actually cum, I thought it was urine and it turned me off because I did not like the thought of peeing myself. Sometime in middle school, when I entered into the world of internet porn, and found out what it actually was, and of jacking off while watching porn and the rest was history!
What was funny is that between the time I figured out what it masturbating actually was, and the time my parents told me not to do it, I was watching YouTube and heard someone say the word masturbate. The exact phrase was "you better not be masturbating". I did not know what the word meant, nor did I look it up, but I did have a teacher named Mrs. Bates and the word reminded me of her. So, loud and proud, I repeated the phrase right in front of my parents, who were again, shocked and had no idea where I got it from and grounded me for a few hours until we went to Peter Pipers and everyone sorta forgot about it.
Those two experiences when I was young taught me to look up things that I do not know of when I first hear it.