I think this cartoon says it all really. 
As others have said, whatever you do, just draw. Something, anything. And no matter what, do not be afraid of failure, mistakes, or having your work look like crap. Making mistakes is the single best way to learn and get better. Just try to be a kid again and draw without abandon.
One good online resource you could consider and I haven't seen mentioned in this thread is Draw-a-box.
As others have said, whatever you do, just draw. Something, anything. And no matter what, do not be afraid of failure, mistakes, or having your work look like crap. Making mistakes is the single best way to learn and get better. Just try to be a kid again and draw without abandon.
One good online resource you could consider and I haven't seen mentioned in this thread is Draw-a-box.