How different does one painting have to be from another in a series? There's no rule, it's down to you as the artist to decide. Only you can know what's appealed to you in the subject, what you want to emphasize or focus on.
Asked in 1905 what colors he used, Monet said: "The point is to know how to use the colors, the choice of which is, when all is said and done, a matter of habit. Anyway, I use flake white, cadmium yellow, vermilion, deep madder, cobalt blue, emerald green, and that's all."
So, equip yourself with a white, an intense yellow and red, a bright blue and green, and get painting!
(Quote source: p196 Monet by Himself, edited by Richard Kendall)
Asked in 1905 what colors he used, Monet said: "The point is to know how to use the colors, the choice of which is, when all is said and done, a matter of habit. Anyway, I use flake white, cadmium yellow, vermilion, deep madder, cobalt blue, emerald green, and that's all."
So, equip yourself with a white, an intense yellow and red, a bright blue and green, and get painting!
(Quote source: p196 Monet by Himself, edited by Richard Kendall)