Learn to Knit - Bind Off
When your knitted piece is finished, binding off closes the stitches so that they do not unravel when taken off the needles.
From beginning of row, knit 2 stitches, insert tip of left-hand needle into first stitch on right-hand needle and pull this stitch up, over the second stitch and completely off the needle. Knit another stitch and repeat process.
Cut the yarn, leaving an 8" end for weaving in. Pull the end of the yarn through the last stitch on the right needle and tug it gently to fasten off the last stitch.