Prototyping images

I'd like to know how C2 Game Developers typically prototype and finish their games. I am at the L plate stage and so i'm still looking for tips and advice on the best workflow.

I was actually thinking about using rough graphic images to prototype and see how the game gels and advances, then adding finished graphics later on when i know for sure that everything works seamlessly.

Thanks and Happy New Year!

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In my little experience, you can work with just colored sprites but in the final size (do not stretch or resize in layout) just to avoid re-arranging everything once you replace them with the final images... but this only if you are not considering collision poligons

I personally prefer to work with final images but that depends on how complex the game-graphics are