For official WCA scrambles hold the Skewb with White on top, Green on the Left and Red on the right. This means the White/Green/Red corner is facing you and will stay in front for the entire scramble.
Cube Notation is letters and letter character combinations to describe specific turns on a Skewb. The purpose of notation is to easily describe an algorithm or a scramble.
Uppercase letters describe one 90 degree turn of one layer the letter represents. If the letter is followed by an apostrophe then the turn is anti-clockwise (counterclockwise)
There are only four Turns to know (Right, Left, Up and Back)
Turns
Right
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Left
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Up
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Back
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Video Guide: