Purchase and install a video-editing software program. Windows Movie Maker, the native Windows video software, is not sophisticated enough to format a commercial. Adobe Premiere Pro, Sony Vegas or Avid are preferred editing suites.
Open the video editing software. Each program will open with a welcome screen. The welcome screen will display a list of project templates. Select "NTSC," which will have a frame rate of 29.97fps (frames per second), an aspect ratio of 4:3 and line frequency of between 15,750Hz and 15,734.26Hz. There will be multiple NTSC resolution options; select the option that the broadcaster prefers. The North American standard is 480i for standard definition. The project will open automatically formatted for a commercial.
Import the commercial into the video editing software. If the commercial needs to be edited, use the software to edit the commercial. If it is already edited, then it can be exported.
Speak to the broadcaster about what format they want the commercial in. Most TV stations prefer the commercial to be delivered on Betacam SP. Output the commercial to a DVD using the software and take the DVD to a video conversion company. They will transfer the DVD to the appropriate medium. This should cost less than $50. Take the commercial to the TV station.