Fill a small container half full of the moistened vermiculite. You need "head space" so that when the egg hatches the chameleon can sit on top of the vermiculite until you "rescue" it once it hatches. Put the lid on the container. If your room is warm enough then you don't need an incubator just put the container in a dark place in that room. Check it periodically to see if it's OK. Don't leave the lid off for long when you check it. You will likely see beads of moisture on the inside of the container.