Pictured here is my first heel, attached to my first cast-on bonnet using ravel-cord.
It's also my first toe! You can see the ravel-cord a little better here.
Why the ravel-cord? Because w/o it I'd need to snip the sock from the cast-on bonnet being careful not to snip the cast-on bonnet. Well...I'm not that careful. But look how easy it is to take off the ravel cord. First find and pick out the knot:
Then, pull one end of the ravel-cord:
And voila, no snipping!
Credits: K for taking the picture when both my hands were busy.
Laura Schickli who's booklet contains the recipes I followed for both the cast-on bonnet as well as heels/toes.