First things first, open up the Glide App Builder and head over to the project where you want to add the timer. Make sure all your data sources are linked up and ready to go.

Decide if you want the timer on a new screen or if you can squeeze it into an existing one. If you need a new screen, just go to the "Screens" panel and hit "Add" to create a fresh one.

On the screen you've chosen, find and click the “+” button to add a new component. From the list, pick the “Timer” component and drag it to where you want it on your screen.

Once you've got the Timer component in place, it's time to set it up:

• Decide how long the timer should run (like 5 minutes or 30 seconds).
• Choose what should happen when the timer finishes (like showing an alert, moving to another screen, or updating a cell). You can set this up in the “Actions” section of the component settings.

Now, let's make the Timer look good:

• Change how the time is displayed (like HH:MM:SS).
• Pick a style and color that matches your app's theme.
• If you want, add some labels or instructions around the Timer to help users understand it better.

Decide how and when the timer should start:

• You can set it to start with a button press by adding a "Button" component and linking its action to start the timer.
• Or, you can have the timer start automatically when the screen loads by setting it up in the screen action settings.

Time to see if everything works:

• Preview the app and make sure the timer starts and stops as you set it up.
• Check if the timer shows the right format and duration.
• Ensure all actions tied to the timer’s completion work properly.

Tweak any settings if needed to get the timer just right in your app.