This is an interesting sweater where the entire right side is striped horizontally and the left side is striped vertically.  Knit the right side first, then pick up stitches along the center edge to knit the left side.  Randomly change colors whenever you feel like it.  This will also work nicely with a similar-weight variegated yarn.  Again, please note that I haven't knit this, so I'm not sure whether there are any little tweaks that need to be made for the pattern.

Superior Pullover, Mixed Striping

Needles: 2.5,  2.5  Size: 48  Gauge:  6 sts  10 rws per 1"  Estimated Ydg: 2389

Yarn:  Filatura Superior in Periwinkle, Turquoise and Lemon.  Sweater is knit in one piece from the front center around the right side to the center back, and back again (right side of sweater is striped horizontally).  Then pick up stitches along the length of the back center and knit out to the shoulder.  Then pick up stitches along the front center and knit out to the shoulder.  Then seam the shoulder, then pick up and knit the sleeve on the left.   Left side will be striped vertically. 

 You will notice there are a lot of seams in this garment.  This is done to ensure that the finished item is symmetrical (i.e., you don't want to have a seam on the right shoulder and not on the left).

Right Piece

Remember to periodically change yarns for random striping.  Edges will be added at the end of the sweater.

Cast on 156 sts.   Work in stockinette (randomly switching colors) until piece measures 16" [row 136].

Place underarm marker.

Work back of piece until it measures 28” (row 256).  Put 54 back stitches on a holder; bind off 24 neck stitches.  Switch to front of piece and work until piece measures 24.5" [row 220] on front.

Front Neck Shaping

On row 221 and all remaining RS rows, dec 1 stitch at neck edge 12x. 

When front reaches 28” (row 256), perform a 3-needle bindoff for the 54 shoulder stitches.  Piece should now be completely off needles & holders.  Note there is no sleeve yet on this side.

Left Piece

Pick up stitches (in a pattern roughly 2 – skip – 2 – skip – 2 – skip) along the back edge of the right piece.  Stop at neckline.  Work (randomly switching colors) until the piece is 13” along.  Bind off all stitches.

Pick up stitches (in the same rough pattern) along the front edge of the right piece.  Stop 21 stitches before the shoulder.  Knit, casting on 1 stitch every other row 12 times (RS rows) at neckline.  Continue to work (randomly switching colors) until the piece is 13” along.  Bind off all stitches.  Seam shoulder.

Sleeves

Left side sleeve: cast on 72 stitches.  Work one RS row. Inc 1 st on each side every 2nd rw 19x, then every 4th rw 18x.  Continue until sleeve measures 14.5"[row 120]. Bind off 144 sts.

Right side sleeve is worked lengthwise:  cast on 2 stitches.  Turn, purl.  Continue working, casting on 2 stitches every RS row, until there are 60 stitches on the needle.  Work 120 rows even.  Then on next WS row, bind off 2 stitches, continue to end.  Turn and knit across to end.  Continue working in this pattern until all sleeve sts are bound off.  This gives you a sleeve whose stripes run down your arm instead of around it.

Neck Finishing

With RS facing, pick up stitches around the collar.

Work desired finish for 3". Bind off loosely.

Work hem & cuffs as desired.  Sew sleeves to garment.

Optional Detached Cowl

Cast on 144 stitches.  Work a k2, p2 rib for 16”.  Bind off.