First of all, you can put your logo on your documents. See Settings > Account. Your name and address should be defined in the Details field under Settings > Accounting.
Then, you can choose among 5 different document templates under Settings > Document templates. You can also define a color for your templates and some other lay-out options.
You can also add your Terms and a footer on your documents. For that, you have to go in Settings > Document and email configuration > you select the right configuration > you go in the Terms and Footer tab of this configuration. You can format the text as you wish (with bold, italics, columns, etc.)
For the Terms:
There is also a checkbox that allows you to "Display terms on a separate page" if you want your Terms to appear on the back of your invoice, for example.
For the footer: