The pattern below is a guideline: I'm not an expert in crochet or sewing and my description is at best approximate. However this is free-form crochet,
the difficulty lies more in choosing the colors/texture than in actually making it. If you lose or gain a
stitch it won't show, and it is very easy to lose a stitch when using fluffy hairy novelty yarn (trust me).
You will need approximately 6 hours to complete the bag, more if you decide to line it.
The trick to get the bird's nest distinctive look is to crochet with several yarns together, this creates a nice blend. Pick one yarn that you will use throughout the entire bag, as an unifying element.