Method for applying by imprinting or patterning an insert of polymer material onto a support layer (30, 30a) with a continuous surface structure or a surface structure which is suitable for being permeated by the polymer material, the method comprising the following steps: - providing a mould comprising at least one base and at least one cover; the base and the cover being suitable for defining with facing surfaces (13, 17), when the mould is closed, a mould impression which is delimited perimetrically by a closing edge which extends vertically from one of the facing surfaces (13, 17) of the mould; the mould impression defining the volume and the surface texture of the insert to be applied to the support layer (30, 30a); - spraying a polymer mixture in the fluid state onto at least one of said facing surfaces (13, 17) of the mould; - introducing the support layer (30, 30a) between base and cover of the mould so that, when the mould is closed, the support layer (30, 30a) projects at least partially from the closing edge; and after that - pressing the cover of the mould onto the base of the mould so as to: - define the mould impression; - perimetrically compress the support layer (30, 30a) by means of the closing edge against one of the facing surfaces (13,17) of the mould; - compress the polymer mixture present inside the mould impression; and - allow adhesion of the polymer mixture to the support layer (30, 30a); - opening the mould in order to remove the support layer (30, 30a) and the associated insert; - trimming a portion of the polymer mixture which, following the spraying and pressing steps, has flowed outside the perimeter, defined by the closing edge, of the mould impression. - providing a mould comprising at least one base and at least one cover; the base and the cover being suitable for defining with facing surfaces (13, 17), when the mould is closed, a mould impression which is delimited perimetrically by a closing edge which extends vertically from one of the facing surfaces (13, 17) of the mould; the mould impression defining the volume and the surface texture of the insert to be applied to the support layer (30, 30a); - spraying a polymer mixture in the fluid state onto at least one of said facing surfaces (13, 17) of the mould; - introducing the support layer (30, 30a) between base and cover of the mould so that, when the mould is closed, the support layer (30, 30a) projects at least partially from the closing edge; - pressing the cover of the mould onto the base of the mould so as to: - define the mould impression; - perimetrically compress the support layer (30, 30a) by means of the closing edge against one of the facing surfaces (13,17) of the mould; - compress the polymer mixture present inside the mould impression; and - allow adhesion of the polymer mixture to the support layer (30, 30a); - define the mould impression; - perimetrically compress the support layer (30, 30a) by means of the closing edge against one of the facing surfaces (13,17) of the mould; - compress the polymer mixture present inside the mould impression; and - allow adhesion of the polymer mixture to the support layer (30, 30a); - opening the mould in order to remove the support layer (30, 30a) and the associated insert; - trimming a portion of the polymer mixture which, following the spraying and pressing steps, has flowed outside the perimeter, defined by the closing edge, of the mould impression.