Over the years, I've had to replace many sliding screen doors because someone crashed through it. You know - you have a party, people go in and out to the backyard, it gets dark and someone closes the sliding screen door.
The next person not expecting and not seeing it closed crashes through, bends the frame and you are left with a $400 replacement cost.
Then I stuck on blue painters tape which is kind of ugly and magnetic stickers that just fell off.
This is why I created screensaverkritters. They are handmade, from recycled cans. You simply attach them to the screen like an earring. You will find a short video and many answers you may have on the FAQ page.