The present invention relates to a cosmetic process for making up or for the non-therapeutic care of keratin fibres, comprising the application to the keratin fibres of a cosmetic composition containing at least one compound or a mixture of compounds, which, when the composition is brought to a temperature of greater than or equal to 40° C., confers on said composition a threading nature dmax of greater than or equal to 5 mm, said composition being, prior to, simultaneously with or subsequent to its application, brought to a temperature of greater than or equal to 40° C.The invention also relates to a packaging and application assembly for a composition for making up and/or for the care of keratin fibres, comprising:i) a reservoirii) a composition for making up and/or for the care of keratin fibres, placed inside the reservoir, said composition having a threading nature dmax of greater than or equal to 5 mmiii) a device for applying the makeup and/or care composition and/oriv) heating means for bringing said composition, simultaneously with or subsequent to its application, to a temperature of greater than or equal to 40° C.
