Hii

After generating the RUC for your AIIMS Registration, you need to visit the official login page. Here is the link for the same - http://mbbs.aiimsexams.org/
Once you open this link, in Applicant login zone, enter you registration Id, RUC and password along with Captcha and proceed to login.
You will be directed to your Dashboard. There you will see step 4, 5 and 6. Proceed to step 4 and carry on as directed.
Pay the fees and keep a copy of the slip.
At last print the confirmation page and keep it safe.
You are done with the registration once you complete all the step.
Incase of anymore doubt, feel free to revert back.

Hope this helps
Thanks!!