Honestly I feel that support is one of the easier roles if you have a decent support champ and your ADC isn't garbage. Just help your ADC get last hits, ward in the right spots, and use any support skills you have when you should. I personally prefer playing characters like Kayle who can support really well early on, but still do a lot of damage and farm pretty easily once the laning phase is over.
If you do everything right (warding, helping w/ last hits, help ADC get kills, etc) and you still get creamed, at least you know that you were doing your job right.
But yeah, there's not really any way to get better with a role other than practice. I tend to swap around between ADC, support, and top lane a lot (not a huge fan of mid/jungling, although I want to learn them better. I tend to play with several friends who are much better at jungling/mid than me though), so it helps to not get too rusty with any one particular role.