When configuring PPSS for your organisation it really up to what methods what you would like for your user when reesting their pasword. You also have the option to allow change of password.

The way configuration of PPSS works is that you for example like your user to chose between two methods, lets say SMS and One Touch, then you first do the configuration of SMS and then the configuration of One Touch (or the other way around).
Good practice is to test the configuration of the first method before starting with the next.