Try putting a frame round your picture before you start drawing. Not a physical frame, just a drawn frame on the paper. Decide what you will draw and what you will leave out. The frame helps you to challenge the pose of the figure, and decide what is important to you to make a great drawing.
The frame allows you to focus on the part of the model's pose that you are most interested in capturing.
To help you do this you can prepare a ‘viewer’ out of a piece of cardboard with a rectangular hole cut out of it. Use the viewer to frame the figure: hold it close to your eye, then move it in, move it out, try landscape, try portrait. Decide on a frame that is going to look good. Once you have decided your approach to the picture, draw the frame on your paper, and draw your selected part of the figure within the frame.
This approach also provides an opportunity to create interesting negative space which can help you to compose your drawing, and help you to create a great result.