At the time of this writing, www.powerpivot.com/download.aspx
will render a document containing links to any prerequisites, as well as the 32-bit and 64-bit versions of the PowerPivot for Excel add-in. Choose the appropriate installer for your Microsoft Office version, and save the installer to a location on your PC. After the download completes, you may execute the installer by double-clicking it from Windows Explorer. The installer will prompt you for consent to the licensing terms and for a user and company name, before finally installing the software. You will know the installer has completed when presented with a dialog similar to Figure 1-1.