For this medium sized zig-zag pattern, crochet in multiples of 25 + 5 (loosely) for foundation chain (ch). Counting your crochet stitches is very important for this design.
Single crochet (sc) in 2nd ch from hook. Sc, miss 1 ch (for beginning and end of rows), 11 sc in each of next 11 ch, 3 sc all in next ch, sc x 11, * miss 2 ch (for all middle dips), sc x 11, 3 sc in next ch, sc x 11 *, repeat * to * until last 3 ch, skip 1 ch, sc x 2. Ch 1, turn.
Sc in same st as turning ch, sc, miss 1 sc , 11 sc in each of next 11 sc, 3 sc in next sc, sc x 11, miss 2 sc, sc x 11, 3 sc in next sc, sc x 11 *, repeat * to * until last 3 sc, skip 1 sc, sc x 2. Ch 1, turn.
Continue Row 2 for thickness of color stripe. Tie off and switch color.
1st Row of new color ONLY work ALL stitches in back loops of sc, ch 1, turn.
Continue Row 2 in both sc threads (as normal) for thickness of color stripe. Tie off and switch color.
This pattern can be adjusted for smaller or larger zig zags. Mostly used for blankets.