PROBLEM TO BE SOLVED: To provide a method of dyeing or decoloring hair which is excellent in applicability when applying the agent to the hair so that agent is easily spread over a whole head, and which can adheres the hair at the lower edge of the hair to each other after application to be capable of preventing a floating state of a bundle of hairs at the lower edge of the hair.SOLUTION: A method of dyeing or decoloring hair comprises the steps of: (1) mixing a first agent containing an alkali material and a second agent containing hydrogen peroxide in a container body of a non-aerosol foamer container to prepare mixed liquor； (2) attaching a non-aerosol foamer to the container body and discharging the mixed liquor prepared in the step (1) from the non-aerosol foamer container as foamy matter； (3) applying the foamy matter to the hair by hand； and (4) kneading the foamy matter on the hair with hand to increase viscosity of the foamy matter which is 3 times or more and 10 times or less as that of the foamy matter when discharged at the step (2).【課題】毛髪への塗布時には塗布性に優れ全頭に剤を広げ易く、塗布後には生え際の髪同士を密着させ、生え際の髪の束が浮いた状態になることを防ぐことができる毛髪の染色又は脱色方法の提供。【解決手段】下記の工程（１）～（４）を有する、毛髪の染色又は脱色方法。 （１）アルカリ剤を含有する第１剤及び過酸化水素を含有する第２剤を、ノンエアゾールフォーマー容器の容器本体内で混合して、混合液を調製する工程； （２）該容器本体にノンエアゾールフォーマーを取り付けた後、ノンエアゾールフォーマー容器から、工程（１）で調製した混合液を泡状物として吐出する工程； （３）該泡状物を、手を用いて毛髪に塗布する工程； （４）毛髪上の泡状物を手で揉み、該泡状物の粘度を工程（２）で吐出された際の３倍以上10倍以下とする工程【選択図】なし
