The easiest way to pay for the early arrival (one day early) is to add the "WP Early Check-in" to your cart when registering for camp. If you failed to to that at the time of registration, but now you need to, you can add the charge in a separate transaction.
*Early arrival covers lodging only. There will be minimal supervision due to staff arriving that same day. Campers will be responsible for their own meals. The first meal given to campers is dinner on the first night of camp.