Here's our first DIY: Sewing your own scarf from a suitably-sized piece of fabric.
1. Get your piece of fabric. Cut it into either a square, a rectangle, or a triangle, of suitable size.
2. Hem. I did my first few with a regular hem.
Then, I tried the last seam on my latest scarf with a rolled hem, using this tutorial: sewing a rolled hem by hand, (or use something else, if you're a machine sewer, as I hope to one-day be. In the meantime, I'm not going to wait until I learn and get a machine.) It's pretty easy, nearly as quick, and a nicer edging, especially for thin/delicate fabric.
2b. Add any decorations you'd like. These could be ribbons (like in this post) in any number of directions, or cloth flowers or other embellishments.
Such additions dress up a scarf, but make it less versatile- it stands out more, and is harder to combine with other scarves.
3. You're ready to use it. Here's my latest, tied on my head. (I'm bad at part 1, it isn't quite square enough to fold to a really good triangle, nor rectangular enough to be a "real" rectangle, but so far, it works well enough as a triangle anyways- there's a lot of forgiveness in this.)