If you are using OpenAthens Keystone
Your own OpenAthens accounts can be used for testing. To add additional identity providers (IdPs) before you are live, enable the setting allow sign-in for identity providers via 1:1 connections for your Keystone connection and add their metadata.
If you are using other software (e.g. Shibboleth)
To test with your own OpenAthens accounts, you will need to add their metadata to your system: https://login.openathens.net/saml/2/metadata-idp/YOUR_OPENATHENS_DOMAIN.
Also see Getting a SAML application production ready.
Testing by the OpenAthens Service Desk
When you submit your site for publication in the metadata our service desk will run some tests based on the best practices and our domain experience to make sure things will work well for our mutual customers. To avoid delays, you should pre-enable access for their test accounts. See Getting production ready with Keystone.