Bring 7 oz (200 g) of water to a boil. Weigh out 15–18 grams of coffee (depending on your preferred strength). Grind to a texture slightly finer than sea salt.
Insert a paper filter into the AeroPress's detachable plastic cap.
Use some of your hot water to wet your filter and cap. The water serves a dual function here: It helps the filter adhere to the cap, and heats your brewing vessel. This can be challenging as the water is hot and the cap is quite small: Hold the cap by its “ears” and pour the water very slowly so it can be absorbed by the filter.