This is where I saw the pattern for band. http://www.redheart.com/free-patterns/blossom-headband#.T6GQVWHRYmk.pinterest
I used cotton yarn and a 3.00mm hook.
And here is the pattern for bow. Use the color you used for outer chains of the band as the main body of bow. Lets call it A.
Row 1:SC in the second chain from hook and then SC in evey chain(16 SC). Chain one after the last SC and turn
Row 2: SC in every stitch. Chain 1 after the last SC and turn
Row 3: Repeat Row 2 9 more times.
Now use the other color you used in the middle of the band . Join it in the last row and do a row of SC on all 16 SC of previous row. After doing a SC in the last stitch chain 2 and do another SC in the same stitch. Continue SC on the side. One in each row. And then turn corner using chain 2. Continue SC on the foundation chain, and then the other side.
Put a long thread in a tapestry needle.
Now crunch the bow in the middle and using the needle go through the bow and then ties the rest of the thread over the crunched part. Give it 10 to twellve rounds then fasten off after securing with knots.
Now sew the bow on the band, and you are done.