I can't tell you anything about processing the gel, but rest assured, there's nothing hard about growing the plants! If you live in the south - anywhere that it will grow (catalogs should tell you its hardiness zone), you can stick it in the ground, water if the ground gets too dry, and watch it grow.
When we moved to a home in southern California, the side yard was a mass of Spanish bayonet (aptly named!). We cleared it all out, and found that under the Spanish bayonet was hiding a solid mass of aloe vera. We transplanted some of it to edge our front sidewalk, and it thrived quite beautifully. We had neighbors coming over all the time to ask for a leaf, and we would reply, "no, take a plant - please!"