crypt is pretty simple honestly, go through prebuild but it's essentially just sitting on top of another remote. So I usually use the convention {remotename}-crypt. It'll simply rename and encrypt anything and then pass it into the remove you already set up. A good way to test it is once you've copied some stuff over with the crypt set up try to mount it using rclone mount and try to read some of your files, it should be fine.
Don't forget to back up (securely, and obviously not on your encrypted share) your rclone config! if those keys are lost than so is your data.