Part 4 of Julie Harrison's Mixed Stitch Stripey Blanket is a really fun one: chevrons!
Chevrons aren't hard; they're just stripes that get bunched up in one place and widened in another. The key is the alternating 3-stitch decrease for the bottom point and 3 stitch increase for the top point of each chevron. That's what gives it that zigzag shaping.
Note that Julie starts the first row on the wrong side of the work.
"1. (On wrong side) Ch 1, *1hdc into next st, 1dc into next st, 3tr into next st, 1dc into next st, 1hdc into next st, 1sc into next st ; rep from * to end.......turn.
2. (Right side) Change colour. ch 1, skip 1 st, 1sc into next st (counts as sc2tog), 1sc into each of next 2 sts, *3sc into next st, 1sc into each of of next 2 sts, over next 3 sts work sc3tog,
sc into each of next 2 sts; rep from*.
...til the last 5sts, 3sc into next st, 1sc into each of next 2 sts, over last 2 sts work sc2tog, turn.
3rd row : as 2nd row, and in same color, working back. (This row strengthens the look of the line, so it really "pops out".)
4th row of chevron pattern:
Join the [green] wool, ch 4, skip 1 st, 1tr into next st (counts as tr2tog), *1dc into next st, 1hdc into next st, 1sc into next st, 1hdc into next st, 1dc into next st, over next 3 sts work tr3tog ; rep from * for rest of row."
At first, making the "mountains" of the first row makes the piece wider. But, not to fret, the zigzag rows pull it back to right.
Find her full pattern at: https://littlewoollie.blogspot.com.au/p/mixed-stitch-stripey-blanket-crochet.html