If you're an Admin in your account, the first step is opening the user menu in the top right of the app and click Settings.
Only admins have access to Integrations
Click the Add to Slack button and Authorize your Slack account
After Authorizing Wake, you'll be able to choose a default #channel and your posting preferences, be sure to save your changes!
You can also customize the integration per Space*. If you navigate to the Space settings menu, you'll see the option to choose a specific #channel to post to, or to prevent posting to Slack from that Space.
Once you're happy with you're default channels, and any customizations by Space, you're all set!