Lay down the basic proportions.
Especially if you’re going for a more realistic bunny, rather than a cartoon one: “The easiest way to approach it is to break the animal down into simple shapes. The best way to do that is to look up a ton of photo references and then think, What shapes do I see in this animal?” says illustrator Chioma Iloegbunam.
To start, draw two small circles that are slightly wider than they are tall. The first will be the head of your bunny; the second will be the body. Both shapes should be relatively close to one another.
Depending on the perspective of your reference photo, you might need to make the body shape longer than you would for a cartoon bunny. The goal is to sketch the circles, squares, and ovals that you see in your reference, so you can then start working on the pose and perspective of your drawing.