New answers tagged drawing
Adobe Illustrator is the way. After that you can export the files from PDF, PSD, and so on. You could use Adobe Fireworks as well.
You can try using CorelDraw X7 which is the software I use, it allows you to easily create vectors and retrace bitmaps images to vectors, also using line strokes it's pretty easy. Inkscape It's a free software that it's used to edit SVG's so you can also try it.
This would be a breeze in Illustrator, especially with the stroke options that you can use to ad in the arrow heads. That is what I would use, although, you could probably get away with some way more basic software.
If you would like to move on from the type of drawing you are doing just now to a more detailed image then try posemaniacs.com they have a huge range of 3D built images that show skeleton and muscles - it really helped me to understand the muscles and the different shapes that the body has. Also try this site ...
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