Always put page numbers into your documents, even drafts. Page numbers help readers keep track of where they are, and they help keep the pages of your document together.
You can choose whether to put page numbers in the header or footer. Your word processing program will let you choose the placement of the numbers and then will automatically paginate the document.
Sample MLA and APA headers with page numbers
Sample memo header with page number
Sample newsletter footer with page number
Related topics:
Page formatting
Headers and footers
Borders and rules