Instructions
Start with the shell. Draw the shell first, with a a narrow area as well and a wider area where the crab will protrude from. The shell often has a spiral point on the back or top. Draw a simple spiral shape to represent that part of it. The narrow area is where the smallest part of the hermit crab is wound around the shell to hold the crab in place. That part is not visible from the outside, but it's a good idea to keep the internal mechanism in mind so that the drawing can be more realistic. You can be creative with the outside of the shell, giving it spikes or making it smooth all over. But, make the opening a roughly round shape.
Create a basic head and body shape coming from the opening of the shell. This part does not have to be detailed because most of it will be obscured by other body parts. Draw a rounded rectangle as the basic body shape. At the top of the body, draw two eye stalks and two antennae. The eye stalks are long, thin cylinders and the antennae are simple straight lines.
Draw the legs along the sides of the body. Hermit crabs have six legs that are outside their shells. Draw each leg with three segments each. The four back legs are wider at the top and taper down to rounded points. Then draw claws at the end of each of the front legs. Draw one claw smaller than the other- not much wider than the top part of the leg. Draw the second claw larger. The larger claw is used to block the entrance to the crab's shell and is much larger than any other part of the leg, so the size of the larger claw should roughly match up to the opening of the shell.
Color in the drawing. Hermit crabs are generally orange, but they can be many different shades of orange. Some are light orange with white spots, some are a medium orange with lighter or darker spots and some are closer to red with even darker spots. The spots are small points all over the crab that may have hairs growing from them. The larger claw sometimes has a purple tint.
How to Draw a Hermit Crab
Hermit crabs are interesting creatures that many people enjoy keeping as a pet. Because they find shells to live in and can change their shells often, there are an infinite number of shell designs that can be drawn with them. Most of the shells, however, have a similar basic shape that the crabs find comfortable.