There no easy way to tow a dead skid steer. If you have electical power and can get the brake to unlock then you can tow it at about 2 mph. Holding the steering levers in the direction of travel helps some. If you need to winch it up on a trailer, soapy water under the tires will let them slide some.
If you don't have power then you'll have to take the brake solenoid off and pull the rod up and clamp it in place.