Put Rutino on your home screen
It opens like a normal app, works without signal, and can remind you. Takes about fifteen seconds.
On a computer
It works fine in a browser tab. In Chrome or Edge there's an install icon at the right-hand end of the address bar if you want it in your dock.
On your phone
Open rutino.kernwit.com on your phone and come back to this page — it'll show the steps for whichever phone you have.