Perhaps the most loathed of knit-related tasks is finishing: edging, sewing up, weaving in ends, blocking...they all get a bad name. I get it, when you finish that final stitch, you just want to be DONE. But, trust me, using some basic finishing techniques will really make your project shine.
Weaving in Ends:
Once you reach the end of your work, cut the yarn, leaving at least a 6” tail.
Pull the tail through the last loop to secure your stitches. Use a tapestry needle to weave the remaining ends in securely into the back of your work. If you are working in rows or garter stitch, there may not be a clear wrong side, so use your pattern for guidance or choose one. Weaving the end into 3-4 stitches in 3-4 different directions will ensure they do not pop out later.
To Knot or Not to Knot:
Some people really like to tie off their yarn. This can work well in some situations to secure your end if your project is going to get a lot of use. However, knots have a tendency to work themselves to the font of your project and always in a place that is super obvious. In most cases, if you are working with a wool yarn, the yarn will be "sticky" enough to keep the ends in place an no tying is needed.
Sewing Up and On
Running Stitch: Thread needle with yarn and work up and down through the fabric with even spaces between the stitches.
Back Stitch: Backstitch is similar to running stitch, except you will work a portion of the stitches back on themselves. Pull the stitch through the fabric and then back into the underside behind where the thread came out. The needle is carried under the fabric to the point of the new stitch, where it is brought up again and back to where the thread was brought up on the last stitch.
There are other stitches you can use, depending on the effect you want. Blanket Stitch and Whip Stitch are both very popular and can be used for decorative edging. Mattress Stitch is the ultimate invisible seam between two edges of knitting, but can be a bit tricky to get the hang of.