Replant your aloe in a good dry soil, not dense, that will allow water to pass freely- a sandy soil would be good. If it doesn't take, this plant is prone to root shock, Superthrive can help with that.
To propagate an aloe vera, you have to cut it. Then you let it dry at the cut area before planting. Be sure to plant them in a fast draining soil. After its planted then water thoroughly when the soil is dry. It can take a month or two to root.