Find an old shirt. =]

Cut of the sleeves collar (I don't know what's the right word but you know what I mean, right?)

Turn the shirt inside oud and make little cuts where I made the red lines at the bottom of the shirt. Don't make them to short, you have to tie them together later.
YAY FOR MY AWESOME PAINT SKILLS!

Take to pieces of the fabric and tie them together, tight.

So this with every piece and this is what it should look like.

(The following is optional:)
Turn the shirt outside in, or something? XD
Make a view little holes on the side of the shirt, where the sleeves once where. Take a ribbon and pull this trough the cute, like on the photo.

Make a bow.

AND DONE! You're old shirt now succesfully transformed in a bag. Carry your stuff in it and have a nice day! =D