Original

Season 15

Season 16

Season 18

Instructions

There are a few qualities that are common to all of the Doctor Who scarves and I have briefly described the techniques to achieve them below.

• Row Amounts: Knitters use the term "row" to describe one pass across the needle. In garter stitch, which is what these scarves are made with, it takes two passes across the needles, or "rows" to create one of the horizontal "ribs." To the right, the yellow stripe has four ribs, which would take eight rows to knit. On my patterns, this would be represented with "8 yellow."
• Yarn/Fiber Choice: On this site I've recommended some specific yarn choices that I have found to be the best for each scarf. You can, of course, use whatever yarn you want, but ideally it should be "Sport," "DK" or "Worsted" weight and preferably a wool or a wool blend fiber. Mixing different brands or fibers together is possible but in some cases it can make for an uneven scarf. My recommendations for the original scarf include some different brands and fibers but I have had no problems mixing these particular ones together. If you encounter a problem you should experiment with different tensions and needle sizes between colors.
• Stitch: The scarves were all knitted in garterstitch and this is the stitch you should use for that authentic look. Garter stitch is probably the simplest knitting technique, as it's all knit stitches. To make the edges smoother, you should slip the last stitch of every row "as if to knit."
• Color Changing: After you finish with a color, cut the end about 10-12 inches long. Knit 3 stitches with this strand, then on the fourth stitch, start knitting in the new color leaving about the same length strand of the new color. (You should have two equal strands of each color.) When you have knitted some with the new color, tie the ends into a double knot. (do not pull too tightly; you don't want to tighten the stitches!) Later, use a yarn needle to weave the strands into the nearby stitches. Cut the ends close to the scarf.
• Tassels: Each tassel should consist of one strand of each of the scarf colors. Fold the strands to make a loop, then with a crochet needle, pull the loop through the inside of the scarf and pull the ends through the loop. (Make sure you pull them tightly.) This is visualized here:
  
• Stretching (or "Blocking"): Blocking is the process in which knitted goods are wetted and shaped. I recommend doing this regardless of whether you want to stretch the scarf or not, as it evens out the stitches and relaxes the fabric, making it drape better. There are several methods of blocking and you can learn more about them here. My preferred method of blocking it to lay the scarf on an ironing board stretched to the desired position, place a wet cloth (not dripping wet) over it and pressing a dry, hot iron down on top of it. Just press the iron down and lift back up, and continue along until the whole scarf is done. DO NOT IRON THE SCARF DIRECTLY, as this can warp the stitches and flatten the fabric. (I have ruined scarves this way!)

  While stretching is not necessary, if you're knitting the original scarf I highly recommend stretching it if you want it to look authentic, especially if you want it to resemble the scarf in season 13 and 14. The only story it wasn't stretched was Robot.