I am writing this post to as I struggled a bit with scheduling the exam.
Step 1:
You need to add to cart and buy "Oracle Foundations Exams for Students" for 95$.
Step 2:
You will receive an email with subject "Your Oracle University Order XXXXXXX Has Been Confirmed". In the email it is mentioned as :
Activation Information
Note: Exam attempt order details will take 24 to 48 hours to reflect in the Exam Attempts Administration tool.
To use the exam attempt, you must assign the exam attempt either to yourself or to others.
To assign the exam attempt to yourself, or to others, you must use the Exam Attempts Administration Tool.
Step 3:
Click the Exam Attempts Administration tool and assign to an exam by clicking the last column "Assign Attempts" little edit or pen picture. You will have to give the same email you registered with and 1 in "Assign Attempts".
Step 4:
you will receive an email with subject "Oracle Exam Attempt Assigned". click on Mylearn and enter username password . -- IMP it took 6 hours for mine to show in the "My exam purchases"
Step 5:
Once it shows you can search 1Z0-811 and schedule the exam.
Good luck
Hope it helps someone.