Downloading:
(1) Before starting downloading make sure what is your system type (32bit or 64bit).
(2) Then just search in microsoft.com with: PowerPivot and download the add-in for your system type.
Installing:
(1) Unzip the downloaded zip file.
(2) Run the .msi file and click on Run and follow the wizard to install it.
Running:
(1) In Microsoft Excel 2013 - Open an Excel file.
(2) Then go to File | Options
(3) Select Add-Ins from navigation and click the drop down list under Manage and select COM Add-Ins and click on Go button. Then COM Add-Ins dialog box will appear.
(4) Mark Microsoft Office PowerPivot for Excel 2013 and click on "Ok". Then you will see the POWERPIVOT menu in Menubar like below:
(1) Before starting downloading make sure what is your system type (32bit or 64bit).
(2) Then just search in microsoft.com with: PowerPivot and download the add-in for your system type.
Installing:
(1) Unzip the downloaded zip file.
(2) Run the .msi file and click on Run and follow the wizard to install it.
Running:
(1) In Microsoft Excel 2013 - Open an Excel file.
(2) Then go to File | Options
(3) Select Add-Ins from navigation and click the drop down list under Manage and select COM Add-Ins and click on Go button. Then COM Add-Ins dialog box will appear.
Image 1: Excel Options
(4) Mark Microsoft Office PowerPivot for Excel 2013 and click on "Ok". Then you will see the POWERPIVOT menu in Menubar like below:
Image 2: COM Add-Ins
Image 3: PowerPivot menu