Insert the screen with the leash end down. Flex the screen so it bulges toward you.
Use a ball point pen to gently push the screen opposite the leash down into the metal ring.
Gently push the screen around the edge until it completely but just pops under the ring.
Gently pull the leash until the screen comes up to the metal ring.
Separate the strands of the leash and remove it by pulling one strand completely out.
Push the cap onto the stem to move the screen to its final position.