We start out with a skein of I Love This Yarn, in no particular color. You can find this product at Hobby Lobby. You will also need a E and H hook, scissors and needle. Oh, and a head to size it on!
Ribbing is the most important feature. We want it stretchy, and made with a smaller hook (just as you would with knitting. Start by chaining 10 with your E hook, turning, and single crocheting in the third stitch from hook. Continue down the chain until you've added 8 sc in total. Chain two more, turn, add 8 single sc in the front loops. Repeat until you've created a ribbing that snugly fits around your head (mine was 37 "ribs"). Join it together in one loop, using a slip stitch. Chain one at the top.
Now you'll finish in the H hook. You need to sc around the top of the ribbing (about two sc per "rib"). I had 74 stitches to begin the next step. For my design, I chained two, then double crocheted around the post, for each stitch around, then slst to first dc.
For the following row, I did a normal dc around, after chaining two, then slst to the beginning dc. Followed by a row of dc around posts, and repeated in this fashion for 7 total dc rows.
At this point I decreased after the initial chain 2. I added two normal dc, then another dec, repeated around for the whole row. The next row was just regular dc around posts. I did this a total of three times.
That's it. You could go ahead and add a final row around an elastic hair tie, as some have chosen to do, or leave as is. My thinking is, depending on how thick or curly the hair is (or level of humidity), it may be more difficult to manage around a hair tie.
The finished product is a snug fitting beanie that will accommodate a messy bun, or man bun, of adults or some children (fits my three year old's head!).
An alternative to the six final decreasing rows would be decreasing rows followed by a row of dc that did not go around the post. You'd finish with something like the hat photographed above.