You can actually do this 2 different ways. You can either hook the phone up to your computer and cut from the internal storage and paste on the SD card OR you can use the File Manager that comes pre-loaded on your D3. If you want to select multiple files at the same time just hit menu when the app is open, click "select multiple" and then click "move" to move them. In the camera app itself, there's an option to have the pics and vids stored either internally or on the SD card.