How to transfer videos from Mac to iPhone so I can post a video to Instagram? I created a 15 second video on my Mac and want to post it to Instagram.

I've tried converting it to Quicktime with iTunes and adding it to the iPhone that way, but I can't see the video in the Photos on the iPhone.

I've also tried reducing the file size and emailing it to myself and opening the email on the iPhone and downloading the attachment, but it doesn't load it to Photos so I can't access the video anywhere on the phone. I've even tried opening the mail attachment video in a video editor on my iphone, "videoshop," which supposedly saves the video to my Camera roll, but again, I can't see the video in Photos, so I can't upload the video.

Mac is system 10.7.5
iPhone 5 with iOS 8.3
You can use AirDrop to send files from Mac to iPhone. You can read more about it here https://support.apple.com/en-us/HT203106