Transfer video from Mac to iPhone?

I have a Mac OS X desktop (Version 10.5.8) which I created a 29 MB music video on using iMovie. I need to get the video on to my iPhone 4 and save it to my camera roll. My usual way of doing this is gmail, but it can only send files up to 25MB.

How can I get the file from my desktop to the camera roll of my iPhone?

Please help

Added (1). Can't use iTunes. Too old on my desktop for some reason

Make sure you have the movie exported from iMovie. When you export it, preferably for iPhones, make sure its mp4. It doesn't matter too much though. Then, look for it in the finder, right click it, click open with, and press iTunes. Then connect your iPhone, then tell it to sync videos and you're all done!