Unzip the downloaded .zip file into a directory of your choice on your PC.
Using a method of your choice, upload the files to your server where WHMCS is installed. Uploading the modules folder and all included subfolders and files to the folder in which WHMCS is installed will maintain the correct tree structure for the addon and associated files.
Once uploaded go to Setup->Addon Modules. If all has been uploaded correctly, you will see an entry in the 'Module' column titled "Domain Pricing Manager - eNom" where the author is Nerdle Ltd.
Clicking 'Activate' will activate the module and create the required database tables.
Clicking 'Deactivate' will deactivate the module and remove all module specific database tables. This will not affect an other tables or their contents.
Please note! Deactivating the module will require any configuration data and settings to be re-entered when reactivating the module.