These are the steps to upload this logo to your invoice:
Go to Admin > Invoice Setup then click on "browse" to select the file, then "upload" to upload the file to the Time and Billing servers. The logo dimensions must be 170 (width) x 70 (height) pixels.
Below that you will see your Invoice Templates, just select a template and check off "show logo."
That’s it! Your invoices will now have your logo on them.