Every knitter is going to have to join yarn at some point. There are two main reasons:

• you need to join a new ball
• you come across a knot mid-ball that you want to make look nicer (they’re usually just knotted together in a very *not* nice fashion. Untie or cut the knot and join them. Don’t just try to work over it – you’ll regret it later and it might even unfasten and your work might unravel.)

The most basic of these joins isn’t really joining the yarn at all. You simply drop one yarn, work the next one and then at some point later, weave in the two tails. 

You’ll need: a project (or swatch), new yarn, something to weave in the ends (either a crochet hook or darning needle) and scissors (missing from this pic because I left them on the sidelines). 

Here are a few pics:

Then weave them in. If they’re the same color, you have no concerns about the yarn showing through on the RS. If they’re different colors, take care to weave the darker yarn through its own stitches. 

Either way – and this is important to avoid holes – start by weaving the ends in opposite of the side they’re on, going across the join. This will create the tightest join and make things firm and without a hole. Here are a few pics:

Now do the same thing for the light blue yarn.

That’s really all there is to joining a new ball of yarn. Don’t fret it – the process is simple and the results are great. See? No holes and no showing through of the other color.