There's no actual installation required. If the download has an installer then you can run that and it will handle installation for you but, otherwise, all you have to do is save the DLL file to your machine somewhere. You can then add the component(s) the DLL contains to the Toolbox with a right-click, allowing you to then add an instance to your forms like you do any other WinForms component. Adding an instance to your form will handle adding the reference for you, or else you can add the reference manually as minitech described.