"We" in the documents means the persons reading the document. For the Quick-guide and User Manual this means the user using ArgoUML. For the Cookbook this means the developer working with improving ArgoUML.

"I" in the document refers to the author and is only used to denote the authors personal opinion. Avoid using it!

Use the active voice.

Use plain rather than elegant language.

Use specific and concrete terms rather than vague generalities.

Break up your writing into short sections, each section dealing with a single topic.

Use the present tense.

Opt for an informal rather than a formal style.