Help with Slipper Sock Pattern

I am working on slipper socks and I don’t understand how to do the following that is in blue.

I know that I do my instep for 8 inches, then cut my yarn. [COLOR=“Blue”]Then I have to Knit 9 from my stitch holder then pickup 18 along the side, knit 12 from my needle, pickup 18 along the other side, then knit 9 from the other stitch holder. [/COLOR]

How do I join the new yarn?:knitting:

Just begin knitting with it, leaving a 3-4" tail which you weave in later.