Slingshot Voice and Fritz!Box 7490

Hi I am new to Slingshot and just getting set up for Fibre

However I can't seem to find settings that I need for my Fritz!Box 7490 to handle the Slingshot voice services.

I had done reading on Geekzone before signing up with Slingshot and it seems that you can do it but can someone point me in the direction of settings that I need?

Thanks!