Crack an egg; catch the yolk in your clean hand, and allow the white to run through your fingers into a small bowl. (This way, if you make a mistake, you won’t contaminate the rest of the whites or yolks.)
Slip the egg yolk from your hand into a bowl reserved for the yolks.
Transfer the white into a third, larger bowl of egg whites. Repeat the process, if needed. Refrigerate reserved whites or yolks in an airtight container for up to three days. (Whites can be frozen for up to two months.)