You can easily verify whether an ADFS implementation is working by using a browser and trying to log on:
https://adfs.yourdomain.com/adfs/ls/IdpInitiatedSignon.aspx
Replace adfs.yourdomain.com accordingly.
Note that in 2016, this no longer works unless you re-enable this feature through Powershell:
Set-AdfsProperties -EnableIdpInitiatedSignonPage $true
Send a link to this post to yourself or a friend.