Method for the customization of a footwear

A method for the customization of a footwear, more particularly a sports footwear, wherein the footwear comprises an upper and a sole, wherein the upper comprises at least one or more portions made of thermoformable material and the footwear includes at least one portion made of a different, non-thermoformable material, wherein the method comprises:

• heating the portions of the upper made of thermoformable material up to a temperature above a first predetermined threshold;
• fitting a foot of a user into the footwear;
• applying to the footwear, at least at the portions of the upper made of thermoformable material, a pressure sufficient to modify the shape of the portions of the upper made of thermoformable material, adapting them to the morphology of the foot of the user;
• while the pressure is being applied, allowing the portions of the upper made of thermoformable material to cool down to a temperature below the first predetermined threshold;
• wherein said heating includes selectively heating the portions of the upper made of thermoformable material of the footwear after the footwear is assembled, while leaving the remaining portions of the assembled footwear at a substantially unchanged temperature;
• and
• wherein, when heating the portions of the upper made of thermoformable material, the portions of the upper made of thermoformable material are heated on both sides simultaneously, from the outside and from the inside of the upper of the footwear.