To set your Status:

1. Go to your Profile icon, top right of the Teams screen
2. Click on ‘Set Status Message’
3. Type in your Status and it's possible to @ mention a colleague to nominate an alternative point of contact if required
4. Check the box to ‘Show when people message me’
5. Select the time frames from an hourly option through to ‘today’ or choose to create a custom one.

Note: You can also set your ‘Out of Office’ from here and this will sync with your Outlook.