Create a new database user in 12.2.9 EBS

Dear all

I'm New to EBS 12.2.9

And i need to create a new custom Database user with privileges on INV and WSH schema objects on the Production environment

while reading i found that the custom schemas should be registered and edition enabled

and we need to use the API AD_ZD.grant_privs to grant privileges on EBS 12.2.9

so i got confused

so dose any have a step by step action plan to create a new database user without causing any issues on the production environment

BR

Hossam