How do I insert page numbers into my multiple page document?

In Office2010 MS Word, click insert option in main menu:  Inert>Page Numbers> then select any one of the options TOP, BOTTOM, Margin etc. Then select position Left, Right or Centre.

The page number will be inserted.

As Khan explained above, in Word, click insert option in main menu:  Inert>Page Numbers> then select any one of the options TOP, BOTTOM, Margin etc. Then select position Left, Right or Centre. The page number will be inserted. Also, after all of those you can edit font type, Bold, Italic,size, etc.