How do I join a new ball of yarn in the middle of a knitting project without a knot?

The most reliable way to join yarn without a knot is the "Russian Join." It creates a seamless, secure connection by weaving the ends back into themselves.

Here is how to do it:

1. Thread your yarn: Take the tail of your old yarn and thread it through a tapestry needle.
2. Split the yarn: Run the needle through the center of the yarn’s own strand for about 2–3 inches, then pull it through so the tail is hidden inside the strand. Trim the excess.
3. Repeat for the new yarn: Do the exact same thing with the tail of your new yarn.
4. Overlap: You now have two strands that are "hollowed out" where the core has been tucked away. Overlap these two sections (where you have removed the core) by about an inch.
5. Knit away: Simply continue knitting with the two strands held together as one for those few stitches where they overlap.

An even simpler method: The "Overlapping Join" If you are working with a fuzzy yarn (like wool), you can use the "Spit Join" (or "Felted Join"):

1. Unply about 2 inches of the ends of both the old and new yarn.
2. Cut away half of the plies from each end (so they aren't too bulky).
3. Overlap the ends, moisten them with a little water (or spit, traditionally), and rub them vigorously between your palms. The fibers will felt together, creating a continuous, knot-free strand.

Both of these methods leave your project smooth and avoid the lumpiness of a knot. Just be sure to weave in any tiny stray ends on the wrong side of your work once you finish your project!