A SUPPORT MAIN!!! I love you already!
I checked your history and I see you are playing a lot of Leona. I like playing her too she is super fun. It can be hard to know when you will win lane though. Don't be afraid to call your jungler for help. Save your CC to peel with instead of engaging all the time (you might already be doing this but I don't know) focus on keeping your ADC alive instead of trying to make huge plays. You will often find that you can punish over aggressiveness. Keep wards up (especially when playing supports like Sona) so that you can see ganks incoming.
When you win lane, push the wave into enemy tower with your ADC and tell them you will roam for a bit. Head mid to try and gank when able to get not only your lane but other lanes rolling too. Just make sure your ADC knows what you are doing so they can hang back a bit. Ward not only bot but mid as well during laning phase to help them. Don't be afraid to be a bit aggressive with your warding. When you spot the enemy jungler top lane feel free to ward his/her jungle so you know when they are close.
Map awareness is paramount as a support! You need to have a rough idea where the enemy is or at least where they are not. I won't lie, it is super hard to rank up as a support main but you can do it. I did, i went from silver 3 to gold last season and got to Plat this season!
