Nancy Marchant’s website gives excellent instruction in stockinette brioche, both one and two color versions.
Great color photos of top and inside view. Also a diagram noting all measurements (11.5” diam when flattened, but you can knit it smaller if you prefer that).
Instructions are row-by-row, then move to a table to indicate changes to MC or CC at which stitch in each round.
9 different beret patterns using two-color stockinette brioche are provided (free), using a variety of suggested yarns and color combinations. Each has a the solid main color defining a repeating pattern. his one is named “ZigZag”.
Other Berets in the series are:
Well worth reading, an excellent resource.