After installing the LATCH base, check the angle indicator to make sure it is centered in green. The base should move less than an inch along the belt path. The base should be installed with either the lower anchors or the seat belt, not both. If installed with the seat belt, the seat belt should not be twisted, and the shoulder belt lock-off should be used only on the side opposite the buckle. Lock-off the seat belt. If using the lower anchors, make sure the webbing is not twisted. When the Doona is installed on the base, the base release button should change from red to green.