1 - Learn basics of 2D Game Art with this tutorials: 2dgameartforprogrammers.blogspot.com
Most tutorial can be done on Illustrator.
This is the result from one of the tutorials:
2 - Search for 2d game art in pinterest. https://www.pinterest.com/search/?q=2d+game+art
You can also follow me :) https://www.pinterest.com/marcomarmolejos/
3 - Start drawing the simplest characters / backgrounds you find and then select the harder ones.
4 - Repeat 2 and 3 until you can do your own drawings that look as good as the samples you found.
This is how far I've got by myself. Let's see how can I improve this year.

