The study reports on a non-vacuum synthesis method for СuGa$_{x}$In$_{1-x}$Se$_{2}$ films for solar energy applications. The films are formed by pulverising chlorides of indium, gallium, and cuprum with selenious acid. To optimise the blend composition of films, it is proposed to age the obtained structure in a sodium chloride solution and to carry out additional selenization of the surface in a diffusion furnace. The resulting layers are investigated using SEM, EDX, XRD, and Raman methods. As determined, the film is a polycrystalline structure of chalcopyrite СuGa$_{0.6}$In$_{0.4}$Se$_{2}$ with agglomerates of porous crystallites. Secondary phases are not detected. The proposed method does not require a vacuum, and it is simple and inexpensive that opens the prospect of using it on an industrial scale for the synthesis of СuGa$_{x}$In$_{1-x}$Se$_{2}$ metal films.