Installing Magento Extensions : Easy Install Guide
"Copying the files" 1) Unzip your extension package 2) Inside that package you'll see 'Step1', go inside that folder inside your FTP app 3) Locate your website's Magento /app folder using an FTP app. You should now have the contents of 'Step1' on one side, and your main website folder (containing the Magento app folder) on the other side 4) Drag the folders from inside Step1 into some blank space inside your remote site (the important thing here is not to drag on top of another folder, or the files will be placed in the wrong location!) 5) You may be asked 'Merge or Replace' by your FTP app. Choose 'Merge' for folders and 'Replace' for files. 6) When that has completed, navigate to 'Step2' in your downloaded package. 7) Using the same procedure, copy the contents of Step2 into the same location in your Magento installation.
"Clear the cache" 1) Go to the System > Cache settings, and clear all caches (click 'Flush Magento Cache' and 'Flush Cache Storage'). 2) Log out. 3) Log in. 4) Navigate to System > Permissions > Roles 5) Check that you have assigned the new Moogeto Extension options to the appropriate roles, and save 6) Navigate to System > Permissions > Users 7) Check that you have assigned the new Moogeto Extension options to the appropriate users, and save 8) Navigate to System > Configuration and then to the specific config page for your new Moogento Extension. 9) At the top, if this extension requires a license key, enter your license key (this will have been emailed to you; you can also find it inside your Moogento account downloads section). 9) Save this page. You should now be setup at a basic level.