I love chevron(s) - knitted or crocheted, whatever. It’s fun, exciting, beautiful, full of creative potential and easy, but - in brioche - it requires a little bit attention.
In this case, the result is a fishbone (macro and micro) texture and zig-zag shape in a form of corset. 2 color braided edges look awesome, but they aren’t necessary. Navy blue/ white combination already smells like the sea, but you can choose any other.
You can wear both sides, like two different tops. This pattern can be used also for warm woolen (spring/ autumn) vest-top. It’s worked in the round from the bottom up.

For shown summer “Navy” top, You need:

1. Basic brioche- knitting knowledge; knitting in the round ( or you’ll learn here  )
2. 32” / 80cm circular needle in US 7 / 4,5mm (this are thicker needles, for airy fabric)
3. Yarns/thread (must be tightly twisted):

• shown top M (L) is made with 4x50gr, 125m/50gr (~ 600m/~656yards) navy blue (main color) mercerized cotton yarn (“Tina”, St George-Serbia), and 2x50gr, 300m/50gr (~600m) white (contrast color) merc. cotton thread (yarn, for crocheting – “Manuela”, St George),
• For size XL and XXL supply more yarns (~700m/~766yards from each color)
• For vest, use woolen DK weight yarn in the same amount

4.12 Stitch markers

Dimensions shown top ( notice: this is very elastic pattern in both directions)
Finished circumference (flat): 30 ½“/76cm, suitable for chest circumference 35”/87.5cm-37“/92.5cm and waist circumference 27”/68cm – size M (measures of girl on photos 92/68cm).
Instructions are particularly given in pattern for chest circumference approximately 33”/82.5cm (XS-for little girls), 34”/85cm-35”/87.5cm (S), 38“/95cm-40”/100cm (L), 41”/102 cm- 42”/105cm (XL), 44”/110cm – 46”/115cm (XXL).
Finished “wave” length: 17”/43cm. You can do it longer or shorter.