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 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.)
You can also define a footer for each document and define that you want to display the terms on a separate page. You can also copy the terms from another document.
You can use your own letterhead paper on your documents, see this article: http://help.lsp.expert/en/articles/2451379-can-i-use-my-own-letterhead-paper-for-the-documents-i-create-using-lsp-expert
And you can adapt the margins in your documents, see this article: http://help.lsp.expert/en/articles/2619722-can-i-adapt-the-margins-in-my-documents