To plant (any) Aloe, first cover the hole in the bottom of the pot with a pot shard, put a layer of sand in the bottom of the pot (2 inches or so deep), then a 2 inch or so layer of compost or any kind of humusy potting soil will do, then finish off with more sand on top of the compost. Plant the roots of the aloe seedling down through these layers, and leave the succulent barely nestled down into the top layer of sand, tamping all around to hold the seedling firmly upright.
Do not water after transplanting–leave the plants for a week or 2 without watering at all. The seedlings will send down roots at this time, roots that would be discouraged by the presence of too much moisture. Once the plants have rooted in, water once a week or so during the summer, but then more or less discontinue watering during the winter. Aloes do best in a shaded greenhouse or indoors on the windowsill with a northerly or easterly exposure. Aloes live on and on.
For more information on transplanting aloes, please read my other blog Step-by-Step Instructions on How to Transplant Aloes and Other Succulents