Never share your own login. Instead, add the other person as a contact with their own login, and choose what they can see. For example, give your bookkeeper invoices only.

1. Log in at billing.goodnservice.com.
2. Open Contacts (on your dashboard, or in the menu under your name) and click Add Contact.
3. Enter their name and email address.
4. Give them a login, and tick only the areas they need, such as invoices or support.
5. Save. They can now log in with their own details.

To remove access, delete the contact. You are responsible for what people you give access to do in your account, so remove people who no longer need it.