Navigate to Portals -> Accounts and click "New Account".
On the new account pop up, click the "Bulk Add" button at the top right
In the bulk add view, you can create up to 20 client accounts at once.
For each account:
Enter the business name
Optionally add clients and their email addresses
Use Add Clients to grant access to individuals
When you create the accounts:
Each business gets its own private portal
Invited clients will receive an email invitation
Your default modules, folders, tasks, and settings will automatically be applied to each new account
Once everything looks correct, click Create Accounts.