I am going to share a work that I have recorded and recorded so that I can help you as well.
I did a step by step without stating the amount of stitches because everything will depend on the size of the foot and the thickness of the thread and the needle. This one I used is an old wire from the circle that is no longer made. Much like the Bella line.
I used a rubber soles that comes with an insole, but it can be done with a crochet soles, or using the sole of an old slipper, or trimming a sole in the rubber, of those that are used for painted carpets. It is in the shoe stores and upholstery.
I started by skirting the insole with crochet stitches using the holes that have already been made. I placed a marker to guide the fixation of the top that is woven separately.
For the top of the slipper I used this graphic.
I fastened the upper part in the insole with low points
After holding the part in front continue to weave low points until it goes around the heel. Use one
Marker as in the photo to orient.
Heel the heel in rounds to the desired height. Then make chains until reaching the front part already fixed in the insole.
Weave low points in the front and then more chains until it is fastened to the heel, completing the back. Lay circular rows of low, in this I did 3 rows, diminishing some points distributed in the back to be well justinho in the foot.