As you slice the adhesive securing the back glass in the next steps, be careful of the following areas:

There's a delicate cable connecting the back glass to the phone, right next to the volume up button. Don't insert your pick here to avoid slicing the cable.

There are multiple spring contacts around the perimeter of the phone. Be extra careful not to insert your pick deeper than suggested in each step to avoid bending these contacts.

If you damage the spring contacts, gently bend them back with a spudger or opening pick so they align with their gold contact pads on the back glass.