PHP Multi Step Registration Form

I have a website that currently has registration implemented but i need it to be a staged sign up process with them filling out there account details as they sign up to the site.

Currently they are presented with a registration form (very basic) then they go to the user dashboard and have to click around to fill out their profile, so i thought in the long run it would be better to create a staged registration where they fill out their profile on sign up? I will also need to integrate a PayPal IPN to take payment for the membership on the registration.

The steps that will need to be created:
1. Account details
2. Locations
3. Profession & Procedures
4. Gallery – Portfolio pictures
5. Promotions & Special Offers
6. Available Appointment Dates

This form I mainly need the first 3 to be required but the rest can be skipped.
All the features are already developed in the account settings area of the website, we need to use those functionalities and create a staged registration form.

The website is built in PHP / HTML / MYSQL