Materials:

Old clothes
Needle and thread/Sewing machine
Scissors
Tailor's chalk (Optional)

Start off by measuring the size of your head. Get the width and the height of your desire, leave an inch for sewing.
If you have a Tailor's chalk, mark the edges where you'll cut it.

Step 1:

And then, it's time for cutting! :)

Step 2: After Cutting

You'll get a rectangular shaped cloth, then fold it once. Get an inch and get ready to sew both sides together.

Step 3: SEW IT UP!

Sew them together. You can use a sewing machine if you're lucky.
For those who are using a thread and needle with their bare hands, first is to be careful. Wear a thimble if you want to.
You can sew them up however you want, even those with poor sewing skills can make a good one. All you have to do is sew them together. Make sure that you'll sew inside the cloth so the sewn part won't be visible.

Step 4: The Fringe.

Mark 2 inch on the top of your bonnet for the fringe. Cut them freely, or 1 inch per cut.

Step 5: Closing the Top.

Now cut 1 inch from the sleeve. Cut it in between to and tie it below the fringe of the bonnet and then you're done!

Step 6: Finished Product.

There ya go! If my instructions are a bit hard to comprehend, you can ask me directly through twitter! Thank you! (That's my little brother by the way.)