BS: I am 17 years old, I got into 5x5 SL around 2 months ago(with a few short breaks due to vacation here and there).

I watched youtube guides on how to do all the exercises that revolve around SL. One day I was doing the OHP and from the corner of my eye I see a dude staring at me. Shortly after, he comes over to tell me that I'm doing it wrong and that I can injure myself. I defended myself by saying that I started with lower weights for a reason, being not to get injured. He offered a demonstration and I accepted it. He picked the bar up from his chin, and just pushed it upwards. While on the videos on youtube, they start from the neck, push the bar up, move the head a bit back and once the bar is above their head height they position it above their head, not just straight upwards.

Tomorrow I am supposed to do the OHP and I'm left confused as to how the exercise should be done.