Instructions
Tap the "Scalpel" button(the image of a blade). A scalpel and an arrow box will appear on your screen.
Tap the scalpel and drag it over to the arrow box. Drag the scalpel along the box toward the direction the arrow is pointing. When you finish, another box will appear. Repeat the process until you successfully cut out the stained portion of the fabric.
Tap the piece of fabric and drag it into the evidence bag. A message will appear indicating that evidence has been logged.