The best way to do this would be to set yourself up as a client with another email under your coaching account. That way you would be able to sign is and access all client's features available.
You can also switch to client view in the app while logged in as a coach. To do so, tap any of your clients' profiles, then tap the icon at the top right corner and choose "switch to client".
We also have this guide on how to use the app as a client.
