How to hide yarn in a crochet pattern

If you are doing amigurumi, which are stuffed and closed off, or any other piece that is not stuffed at the end of the pattern, you will still have a yarn tail that you need to hide for a nice finish. For pieces that are not stuffed or attached, you will have 2 sets of yarn: one coming from the magic ring when starting, and one from the last stitch, typically ending in an invisible fasten-off. 

To hide the yarn, we will thread a needle through this yarn on the inside of the piece. You will thread the needle on the back loop only of the stitches, going perpendicular to the rows for a few rows. 

To make sure the yarn is securely fastened and it won't open now, go perpendicular to that direction with the direction of the row through the back loops, only using the tapestry needle. Once you go through enough that you feel the end is tight, you can use a pair of scissors to cut the yarn close to the pattern. You can wiggle it slightly to make sure the edges are seen, and it is secured within the crochet pattern.