From the Knit Picks Website:

Wear some Christmas magic around your neck with the Christmas Surprise Scarf. This Illusion pattern will keep everyone guessing. The simple stripes are festive in vibrant holiday colors but view it from another angle and SURPRISE - you’re wishing everyone a HO HO HO-liday with a beautiful evergreen. Also known as shadow knitting, illusion knitting is easy and fun. Whenever you want to “pop out” is purled on the public side, which creates a raised stitch. All around these pulled stitches are knit stitches which form a “valley”. When the project is viewed from any angle, other than straight on, the design pops into view. Surprise!

Each row of the design is actually 4 rows of knitting. This is necessary to create those valleys from which is the raised purled stitches can be seen. This makes the design elongated when charted, but normal when viewed in the project. The scarf is created in 6 panels and each panel is approximately 10.5” long and you can knit the panels in whatever you choose. This allows you to modify the length of the scarf for the wearer - more panels for your tall teen, less panels for your toddler.

Those you meet will marvel at your talent and skill. Even experienced knitters will ask“How did you do that?”. This pattern is both charted and written out so everyone can have a Merry knitting adventure. This detailed pattern will answer all your questions and is filled with tips for success.