The instructions here are the rough version I posted on a forum some time ago - let me know if it's not clear enough.
I made it by pulling apart an old jolly jumper, used the blue bar and the door attachment. tied some strong ribbony stuff thru the holes in the bar to attach to an elastic thing that attached to the door hanger bit and made a hammock out of calico and tied thru the same holes... lol - is that completely confusing??? (ETA: I used the elastic strap because i didn't like the spring on the jolly jumper - i'm using the spring again now tho with this bub)
I bought the calico in a packet, precut from spotlight, I think it was 3m x 90cm - the base of it is about 30cm wide and all i did was to hem the long edges, fold the fabric so that there were three layers in the middle then loop over each of the ends, triple stitch all the seams and thread the ribbony stuff thru them... rough diagram attached, hope it doesn't just confuse more!!