Method for manufacturing a casing of an aircraft turbomachine, the casing including an annular shell extending about an axis A and made of a composite material including fibres that are woven and immersed in a resin, the annular layer including an abradable material arranged inside the shell, and covering a first inner annular surface of an intermediate section of the shell, the method including a step of gluing the layer on the first surface, during which the casing is heated and compressed by a system that is present at least partially inside the casing, wherein, prior to the heating and compression of the casing, a forming tool is mounted inside the casing and is made of two rings.