design for a result is art fundamentals: form vs function --begin with reference/copying and then you advance them with your sense for abstraction.
principals of motion, color theory, composition, harmony, contrast, focus, and timing/rhythm
again, fundamentals you can pick up on within a few hours with online videos.
References are not just real-world; it can/will be other artist work you may try to relate with or emulate. Utilization becomes 2nd nature which is why techniques and methods are the areas for teaching/sharing.
practicing can be to take a screenshot of a game you like and make a fire or explosion for it that harmonizes or contrasts with it