A method for spraying a mixture comprising at least a first liquid in the form of a liquid preparation of water-soluble or water-swellable polymers and at least a second liquid, characterised in that it utilises a nozzle (1) for simultaneously spraying the at least two liquids, comprising: • a body provided with a first chamber (2) in which a first liquid flows and a second chamber (3) in which a second liquid flows, each of the two chambers having a through-hole (4, 5) opening on the outside of the body, • a deflector (6) secured to the body arranged downstream from at least one of the through-holes (4, 5), opening in the direction of flow of the first and second liquids, said deflector being capable of modifying the direction of flow of the first and second liquids. The invention also relates to a nozzle for implementing the method.