Take the notch side of the transparent screen facing inward (the side with steps) and tear off the upper protective film and install it in the upper shell limit frame (Figure 1), and then paste the protective film back, as shown in Figure 2.
Take the screen gap face in (with a step side) and tear open the upper protective film to install in the upper shell limit box (Figure 1), and then attach back to the protective film, as shown in Figure 2.
Take out the protective film with the notch face inward (the side with step) and tear off the upper protective film, install it into the upper shell limit frame (Fig. 1), and then paste the protective film back, as shown in Fig. 2.