How can I practice drawing the human body?

Best format of practicing Human figure is News paper take sketchpen your hand and start outline to that figure with diffirent action figures specialy in sport section now you have to try same out line on any rough plain paper.
* it will imprve your skills of action figure 
* Improve and update latest figure styles and clothings and all
* You will under stand folds bends in body posture and clothing

All the best try and reply

Use an anatomy book to understand what's below the surface but think about each muscle in 3D. Don't draw the muscles as a series of lines. Draw them as sculpted spheres, boxes and cylinders. With that being said, you don't always have to actually draw spheres and boxes on the page.

Start from studying your own body and see yourself in mirror by know your body you can start understanding more or less every human has similar features but at the same time distinct features . Gradually once you made an habit of that ,shift to great masters like Leonardo , Michelangelo and Indian yogic poses for excercise from there learn how human figures bend and structure is . 

You can practice drawing of you hand and fingers.

take a mirror and look your face with different expressions.

and try to draw those expessions nose,eye,leep etc.

and you can draw human figure drawing with the help of your family member tell the to stand and give different poses.