After Cilla wrote down the notes, she decided to practice the incantation. She muttered under her breath, "Ap-toh press-soo-rah, Ap-toh press-soo-rah, Apto pressura." She then picked up her wand and carefully drew a downwards vertical line a few times until she felt confident. Cilla took out her potions equipment and used the cleaning spell to make sure they were fit for use. Cilla donned her now clean gloves and pointed her wand in her cauldron and said, "Scourgify." Now her cauldron was nice and clean so she placed her clean thermometer in the cauldron before filling it halfway with water using, "Aguamenti," until the cauldron was half-full before saying, "Finite." She then lit a fire underneath the cauldron.

Cilla then made the vertical movement with her wand as she said, "Apto pressura." She carefully looked at her thermometer and much to her relief, the temperature had not exceeded 100 degrees Celsius and it wasn't boiling.