How do you draw a coke bottle?

Just draw a cylinder with a "funnel" on one end, rounding the transition point from the cylinder part to the funnel part. The base of the cylinder part is rounded and bumpy. That works for for a plastic Coke bottle. If you mean the glass bottles, they are similar, but yet harder to draw, and require more detail. On them the transition to the "funnel" part is more gradual and more like a cone. There are the grooves on the side, and the bottom is thicker and doesn't have the "bumps."