How do you get rid of an electrical outlet?

Just make it a junction box. Remove the outlet, tie the blacks together under a wire nut. The the whites together under a wire nut. Tie the ground wires together under a wire nut. Push all the wires back into the outlet box and cover it with a blank cover. Paint the cover the same color as the wall. Do not sheet-rock over the outlet box. All junction boxes must be accessible.