Before placing back the board you may want to remove a plastic film that protects new glue for the components

Put the board back in place until it sits firmly standing in the groove, the glue should also keep that in place

connect back the ribbon cable

place the speaker back and secure it with the eight screws as in step seven.

As you can see from the picture if there are cables or films that are in the way while you assemble your phone, you can use tape to help you out