While the clay is air-dry and does not need to be fired, if you would like a more resilient final piece, it can be fired up to 1250°C.
If this is the look you are going for, then we suggest reaching out to local pottery studios and asking if they will fire your piece for a small fee. Your work will need to be fired twice - first as a 'bisque' at around 1000°C which hardens the clay to prepare it for glazing, then again after applying a glaze.
If you're firing the kiln yourself, follow all manufacturer instructions and please make sure that the kiln is well vented (i.e. suitable extraction fan and canopy fitted allowing fumes to be safely removed from the kiln room).