The Make 1 set of stitches are great if you need an invisible increase in your knitting such as in the Twist Collective Caeles tank top.

Make 1 Left
· Insert left needle from front to back under strand of yarn which runs between next stitch on left needle and last stitch on right needle
· Knit this stitch through back loop

Make 1 Right
· Insert left needle from back to front under strand of yarn which runs between next stitch on left needle and last stitch on right needle
· Knit this stitch through front loop

Make 1 Purl Left
· Insert left needle from back to front under strand of yarn which runs between next stitch on left needle and last stitch on right needle
· Purl this stitch through front loop

Make 1 Purl Right
· Insert left needle from front to back under strand of yarn which runs between next stitch on left needle and last stitch on right needle
· Purl this stitch through back loop

Learn one way of doing a central double increase with WEBS Yarn Store designer Kirsten Hipsky. This technique is used in Valley Yarns Pattern Hearts of Oak series of patterns: Christmas Stocking, Scarf, Cardigan, and Hat.