Open your video editing program, and locate the video file that you'd like to convert. Select it, then click on "File" in the top menu bar. Scroll down, and click on "Export." In the list of export options click on "Using Quicktime Conversion." (NOTE: In some cases there might be a "Quicktime Movie" option also. For this tutorial, skip that option and go with "Using Quicktime Conversion.")
Click on the "Using Quicktime Conversion" option. The Quicktime menu comes up, and the name of your movie appears in the "Save As" bar. Down near the bottom of the menu you'll see the "Format," & "Use" tabs. The tab we'll be focusing on is the "Format" tab. It should read "Quicktime Movie," and have a button next to it labeled "Options."
Click the "Options" button. The "Movie Settings" menu pops up. This is the menu that you'll come to any time you want to make an adjustment related to the size dimensions, audio settings, or video format of a movie that you're wanting to export to DVD, or upload to the internet. To change the the file format of your movie, click the video "Settings" button at the top of the menu.
Watch as the "Standard Video Compression Settings" sub-menu comes up. This is the sub-menu that controls all things related to video formatting of your movie. You can adjust the frame rate here, raise or lower the compression quality, and alter the data rate of your compressed video. To change the file format itself, click on the tab labeled "Compression Type," right at the top of the menu.
Watch as the tab opens a list of video compression settings. Scroll down until you find "MPEG-4," and click on it. "MPEG-4" will now appear as the listed setting in the "Compression Type" tab, and some of the video sub-menu presets might change. Make any further adjustments that you'd like to the data, or frame rate, and then click the "OK" button at the bottom right-hand corner of the menu. You're now ready to export your video in the MP4 format.