Portal 7.0 to 7.3 upgrade

Hi

We are on Solaris SPARC 64 bit servers, with Oracle DB.

We are upgrading Portal 7.0 to 7.3

Can someone provide the step by step guide for portal upgrade from 7.0 to 7.3.

I am new to Solaris so, plz let me know if there is something specific which is required for Solaris.

Thanks