The La Gran Striped Pullover is worked in stockinette stitch, but not all stripe patterns are. Here are a few different ways of incorporating stripes into your patterns. For all techniques, begin working the new color at the beginning of the row. You may want to tie a knot temporarily with the two tails so the edge stitches don't elongate. When you're done knitting, untie the knot and weave the ends into the fabric knit in the same color.
Stockinette stitchto change colors, just drop the old color and work across your row in the new color.
Reverse stockinette stitchwhen creating stripes in reverse stockinette, you have options. The first is to work the stripes as you would if you were working in stockinette stitch, which will create a row showing both colors (1). To avoid that, try this: Change colors on a right side row but knit across rather than purl (2).
Garter stitchon a right side row, just drop the old color, and work across in the new color.
Ribto prevent the two-colored stitches on a right side row (1), abandon the rib pattern temporarily, drop your old color, and knit across in the new color. On the next row, work across in the rib pattern as before (2).