Create and save default options in Excel 2007

This is off today’s topic, but I cannot figure out how to save the options I set in an Excel 2007 worksheet so that any new worksheets in that workbook, or in new workbooks will come up with those settings. E.g., worksheet size – 75%, font – 12, row height – 22, grid lines color – 50% gray. This can be set in one worksheet, or many can be selected and all set at once, but it doesn’t save. Am I missing something?