Single Sign On Service for clean website

[Ahsan Jewel]

Hello, we have some 4-5 websites in our school, all of them are accessed through username/password. Now, if I want to use a Shibboleth IdP for establishing Single Sign On for these websites, what actually I need to do? 

For your kind consideration: all of those websites are running for last 5-6 years. 

Thanks,

Ahsan