When you start sketching, don't worry about being too artistic. You want to learn to observe the cat's basic structure, so begin by sketching these in simplified forms. These can change dramatically with a cat, due to their great flexibility. Rough in the oval of the ribcage/belly area, the shoulders, rump and head. Observe the cat in various poses, mentally simplifying the shapes - curling in a ball, stretching, arching. Note that the spine runs from the back of the neck to the tip of the tail, and while very flexible, won't form a sharp bend - this is a useful line to observe in sketching, helping you align the forms of the body. The tail is an important means of expression for the cat, and aids in balancing, so should always be included in the sketch where possible.
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