First ensure you’re in the firms account (the current name is visible on the top left corner of the screen)
Then hover over Settings from the top menu and click Advanced
Within Advanced Settings you can then change the name of the firm by changing the 'Company Name'
Within Advanced Settings you can also:
Add a Logo
Add a link to your website
Add your email address
Add your name
Edit your main industry sector (This should be "Accounting and Auditing Activities")
Change your Financial Year