How do you easily make an eraser yourself?

Answer

An eraser is made of soft rubber.

By the way, “Rubber” is an English word meaning “rubber”. The first thing the discoverer of rubber noticed was that you could rub pencil away with it! The softer the rubber, the better, but it goes with all rubber, for example with a rubber band.

What also works well to erase pencil is breadcrumbs.