Variable ZigZag Line 

Draws a Zig Zag line straight ahead from where the turtle is pointing.
4 variables.
peakAngle - Angle of each peak 20-60 degrees usually works well.
swingBack - how much to swing back each time to get the peak angle correct
stitchCount - each "stitch" in this case is two peaks.
stitchSize - length of each stitch. Usually 8-25.
stitchSteps - how many stitches of stitchSize between each peak. 1-3 works well.
Leaves the turtle pointing in the same direction as it started.