Your client wants to open a new QuickBooks Payments merchant account. From inside QuickBooks Online, where can they go to sign up?

In the usage tab of account and settings.

Explanation:

First and foremost, in order to open the new QuickBooks account, the individual would have to create an account. The first step to open the particular usage tab for QuickBooks then open the account and settings. They'll sign up in the usage tab of account and settings.

After this has been selected, they can then create the account using their names and then providing every other necessary details. Then, for payment purpose, a debit card or credit card can be added. Then,the necessary transactions can be carried out.