Mine was about the same size when I got it.
All I did was fill a 3 gallon nursery pot with the AV Mix, secured a pole in it with the tree fern attached and stuck the end of the cutting down in the center a few inches and tied it to the pole.
Roots will continue to sprout out along the entire vine along with new leaves
I heavily mist it every day and feed it once a week. When I feed it, besides spraying the entire plant to get all the roots, I also pour some right down through the top of the tree fern totem.
Don't know if I'm really accomplishing anything by doing that but the plant seems to like it