*Some good information for playing AD with various supports, how to play with Janna, how to play against aggressive lanes, support basics, last hitting under tower as a support and micro-management.
A tutorial/explaination on Leona. A bit more from the tank perspective than support.
A tutorial/explaination on Sona.
Warding is your friend. Warding saves lives and wins games. Ward.
Xpecial’s Support Tutorial Series SERIOUSLY WATCH THIS
A very general tutorial giving you an overview of supporting, basic runes, and how to play without a lot of detail.