Tips for promos

I started playing lol a year and 1/2 ago. I sick at the game. Not going to lie since I'm in elo hell and kept losing shit tons of ranked games. Not that bad in pubs though. I'm on a 4 in a row win streak. 82 lp. Close to promos. Just by practicing decision making with ww and tryndaqueer(last game with him was tryndafeed due to 3k ping so I had to reset and I came back to be welcomed by a 6 and 1 garen who I was crushing in lane before the lag and we still won. All I did was split push and proxy farm). I main shyvana who is the new udyr. I've been having success with devour jg. ww, yi, and shyvana. ww is all about team work. Yi is greedy for 1v5 pentakills. Shyvana is just get Hydra and do insane dmg and tank hits. She's also hard to kite. Trynd is trick2g udyr strategy and is also decision making in my opinion. I'm learning more for sure. I'm in B5. I'm almost free. 1 more win and promos. 2 more afterwards means promoted. Then I will ascend from the depths of elo hell into silver. I'be never done a league series outside of placements. What are some recommendations to win.