Baaaad, make sure you use a reference, don't try and draw out of your head wink
Well, that's not entirly true. You don't -have- to use a reference for your art to be good, it might help, but...*shrug* Oh, and big tip here. Remember, people are 3-dimensional, try to incorperate that into your drawings.
Needless to say that you need to practice. But I would work on the head and hair more than anything eles since that's what usually pulls the whole picture together. The head shape...there are plenty of good tutorials like polycarbon to help you with that. The hair looks like pieces of yarn from a ragdoll. sweatdrop
I would echo the other's and say that reference material would work wonders. The pose here looks stiff and unnatural, especially the arm and hand.
And finally...the wind is blowing in two different directins in your picture. It might help if your picture abide by the laws of physics. biggrin