I been googling videos and notes regarding the sketching of geometric figures, such as: planes, solids, 3rd/ 2d geometric shapes. Could not find decent resources. The reason i ask is that I am having a hard time picturing certain problems with my mediocre drawing skills and I also tutor so it is sometimes easier to draw a person a picture. Ie 3d image of cross-sectional volumes in calculus or figures in sterometry. I soon will be taking Calculus 3. It is not the math or the theory that is bothering me. It is lack of intuition i can generate from taking an object and simplifying it to its most general case geometrically. Also helps with physics problems. Thanks.