How to “thread tail through remaining stitches”, “pull through”

This is a skill that every knitter needs to know and it's very simple. 

Use the working yarn that you’ve been knitting with. Cut off the yarn, leaving a couple feet or more. Thread the end into a tapestry needle and pull that through the remaining stitches on your knitting needle.

When all of the stitches are on the yarn, pull it tightly like a drawstring.

Tutorial Video