Here's how to do it:
- Navigate to the News section and tap on "Add a New Post".
- Write the content of the post, and tick "Send in-app notification". Once that's ticked, tap on "Send push notification".
- In the push message option, write the message that you wish to push to your clients, and tap on "Add" when you're done.
- Next, tap on "Submit" to send the message as push-notification to all your clients.