That wouldn't be an easy thing to do.
I think my young self would be freaked out at seeing an exact copy of me, same voice, same height, same face, but more muscular and a bit older; and he would try to kill my current self. It would be a weird fight because my current self would know more fighting tactics to win, so my young self would be like
"You blocked all my attack moves! Who are you!" Then, my young self would grab a weapon and attack. My old self would be like, "Do I have to use my ninja moves against my young self and knock myself unconscious to survive? I don't want to hurt myself because what if it's a permanent injury?" If I break my young self's wrist, my current self's wrist will have an old injury.
I'd run and let my young self chase my current self. I'd be like, "It's me! Stop trying to chasing me!" My young self would say "Who are you! Who sent you?" I'd be like, "I am you from the future. I know all your secrets." My young self would be like, "I don't believe you!" Then, my current self would have to talk about the secret Hustler magazine stash and then my young self would stop running and be like, "Man, no one knows about that."
I am not sure if advising my young self would change the future for the better. Like, there was this nice girl I met in college. I didn't pursue it farther than being friends. What if that would have been the worst thing to do? Then, I would want to go back in time and advise against that. The mistakes we make in life, hopefully, we learned from them. If we don't make them earlier, we may make them later and with a possibly worse outcome.