Log into an account that has admin access to redshift. Because Redshift does not support granting permission to all schemas, if you haven't already, it's generally best practice to create a hyperquery user within an existing user group that gets access to new schemas as they are created.

Once your user group is created, create a hyperquery account within this usergroup by using the following command:

create user hyperquery password '<type_a_nice_password_here>' in group <yourgroup>;

... replacing <type_a_nice_password_here> with your password and <yourgroup> with the name of your user group.

To learn more about Redshift grant statements, see AWS's documentation here.