There are three pieces to the AeroPress - the plunger, the brew chamber, and the black filter cap. Place plunger down, rubber side up, and squeeze brew chamber over plunger until the rubber creates a seal.
Add your ground coffee to the brewer, place the brewer on your scale, and tare your scale.
Start Timer. Pour all 250g of water into brewer and stir to fully saturate the grounds. Screw on the cap, with the filter inside, onto the brewer.
At 1:00, flip the brewer over and place atop your mug or carafe. Press down on the plunger with an even pressure to slowly push the water through the bed of coffee. When you hear a hissing noise, stop pressing. This press should take about 30-40 seconds. Remember - choose a sturdy mug or carafe!