Drivers: press Edit in the driver's row on the Drivers list, or Edit at the top right of the driver's page. Change the name, mobile, employment, home depot and licence number, class and expiry, then press Save. Pay, tax and bank details have their own cards on the driver's page.
Staff: press Edit in the person's row on the Staff page to change their name and mobile; change their role from the Role list in the row. Login emails are the person's own: they change them under My account. Someone who also works for another company keeps their own name and mobile, which they change in My account.
Vehicles, customers, subcontractors, depots (Settings, Depots) and rate cards each have an Edit button on their row or card too.