How can I get better at top?

I feel like, since season 5, my performance as a top lane has decreased dramatically. I rarely play ranked, but when I do I end up in low silver with a 50/50 win record. I know I can do better, and part of it is on my really poor computer, but I know I'm also missing a kit of major components to the macro game that I feel competitive players have.

Can anyone in higher elo, preferably a top lane main, provide me with some tips please?