[left]HladekStepan,
No problem. 
The main thing I really think that you need to do is to look at reference - have you done so? Reference is really key once you’ve gotten past the initial concepting stage. Google is your friend in this regard, as well as the reference links I posted to the first post of this thread - check out Ben / justmeina’s gallery, there are excellent male reference photos there.
Do you have any experience drawing from life? One thing I really recommend doing if you can is to attend life drawing sessions or classes and also to do master studies. Check out the Personal Sketchbook area of this Forum and create your own if you have not already to keep a record of your progress as you do life studies, master copies, and draw the figure from reference. It just takes a lot of time and dedicated practice to master the figure, but of course it is possible. Just check out others’ threads who are on the same road, and diligently studying the figure. 
Hope this paintover helps - the main thing is to elongate your forms, and to let them breathe. Take a picture of yourself in the same pose, or of a friend, or just use reference to get the details and the overall shape right. The gesture is the most important thing first, the overall sweeping line of the action of the pose.
In the PO I also extended the composition to make it more interesting. You want everything in your composition to reinforce the central subject, which is here the giant. Make the hills and mountains echo the movements of the giant and complement his form. All compositional elements should serve a purpose, and not simply ‘be there’.
You might want to make the roots of the hills above his head into his hair, sort of entwined around his head. This is just a suggestion. 
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Here is a larger scale jpg of the PO:
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[left]http://i23.photobucket.com/albums/b380/rebeccak5/OFDW%20019/HladekStepan.jpg
Looking forward to seeing more of your progress! 
EDIT: More crits to come!
Cheers,
~Rebeccak
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