Use quality paper. Some students have used paper with borders or graphics. This is fine, but make sure the finished product is easy to read. Be sure to include the signature paragraph, signature line, and date line after your answer the last of the background questions. Do NOT staple or bind your application.
Paper clips are preferred.
Very carefully proofread the entire document. Check also for overall appearance including margins, awkward page breaks, font size and type, etc. Now review your entire application once more.