Use the Margins page found in the worksheet's File | Page Setup to set page margins, header and footer positions, and centering.
Use the Margins (inches) options to set the page margins for all sides of the printed page. Set the Left, Right, Top, and Bottom values in inches to any limits the printer allows. The margins are for the worksheet printout and are independent of the settings used for Headers or Footers. If the Top or Bottom margins are set to a value lower than the header or footer it is possible that the text can be overwritten.
The Center on Page options automatically center the printout Horizontally, Vertically, or both. If this option is not used the worksheet prints in the upper left corner of the page.
The From Edge options controls how far the Header or Footer is printed from the edge of the page. If these values are greater than the Top or Bottom Margins it is possible that the worksheet data can print over the header or footer. The text that is printed for the header and footer is controlled from the Options page.