How to stick back the screen to body of watch

Hi Nelson,

If it's just the adhesive that's failed and everything else is intact including the Force Touch sensor, then you can just buy replacement adhesive here on iFixit; just click on the Apple Watch - Series 3 picture on the upper right hand corner of this screen then scroll down to Parts and select Adhesives. You'll need to pick which one is correct for your watch, the 38mm or the 42mm version since they're not interchangeable.

Apple Watch - Series 3 Adhesives

If your Force Touch sensor has gotten damaged, for a bit more money you can get a replacement for that as well.

One thing to take note of, however, is that the main reason I've seen that the displays come off of Apple Watches is from the battery swelling and pushing the screen off. If that's the case with yours, you will definitely need to replace the battery before you do anything else; a swollen battery can be a fire hazard; just ask anyone who owned a Galaxy Note 7! A good battery will be a nice, flat rectangle whereas a swollen one will look pillowy and puffed up.

If you do end up needing a battery you can buy that as well. I'd recommend the Fix Kit version, as it includes both the adhesive and the Force Touch sensor, along with all the tools needed to do the job right.

Apple Watch - Series 3 Batteries

To select the correct battery, you'll need the size - 38mm or 42mm - and whether it's the GPS or Cellular model, as it appears they all take different batteries.

If you go to the Device page for your watch, you'll find guides for any of the three possible repairs you're looking at; just the adhesive, the Force Touch sensor replacement, or the Battery replacement.

Apple Watch - Series 3 Repair - iFixit

Sorry I couldn't be more specific, but without the details of your watch this is the best I can do.

Good luck with your repair; let us know how it goes!