When I started ranked, I really wasn't any good. I didn't even understand what a good team composition was. Going 1-6 every game and dropping my Elo to 800. Now with much more experience I'm going 15-2 almost every game, but can't carry my team due to trolls and people who AFK/DC. What can I do to get my Elo up with unskilled Players on my team that drag me down every game?

Why would you play elo without fully knowing the game?

Just keep playing, don't go full tilt. Also, elo doesn't matter, but if you want to raise your elo, play 1 role, exclusively, learn 3-4 champs for that role, and learn how to be a better than average support/jungle. If someone takes your desired role, most people won't complain if you volunteer to jungle or support.

you should't have started playing ranked if you weren't serious you deserve your elo.

Carry harder, play lots of games.

You're not a troll, so your team is 20% less likely to have a troll in the game. Therefore in games were trolls determine the result, you are at an advantage, and when they're not, you're playing above your Elo, so you should carry.

Remind people to buy wards, and play champs that can start and determine the outcome of teamfights, like Morgana mid, Amumu jungle, etc.

Find the one role that clicks. Kills do not equal wins. Shutting down the opponent does more than getting fed yourself.

Get better at the game. There is no such thing as elo hell.

I have played 500+ games of ranked. My highest elo is 1400 and my lowest is 1150. The only way you'll get your elo is 800 is by not being skilled enough to keep it higher.