Jib Jab is a wonderful service that allows users to replace faces in their movies and videos. However, for most of the videos in their library, you need to subscribe. Sadly, i am a complete cheapskate and won't pay the $12 a year a subscription costs. Using software i already have, i will show you how to make your own video starring yourself!
Step 1: Starting Up
First of all, you will need a headshot and a video with people in it. Import those with ctrl + I. I used The Green Bouncy Inflatable Green ball by NigaHiga, and a picture of a very handsome gent who I'm not quite sure who it is. Looks oddly familiar. Hmmmm. (it's me) Anyways, click and drag them to your timeline and resize them so that the video takes up most of the screen and
Step 2: The Mouth Movement
In this step, We are going to create the mouth movements. if you don't want that, skip this step. First off, duplicate your head layer. Take the topmost layer and crop it down so only the bottom lip and down is showing, like in the picture. Then take the bottom layer and crop it down so only the head is showing. Now, right click your video (or whichever layer has the audio) and choose keyframe assistant > Convert audio into keyframes. That should create a new layer which will tell other layers to move according to the audio. Now, click on the new layer and go to Effects > Both Channels. Now go to Mouth > Transform > Position. Click and drag the swirly line to the stopwatch at "Both Channels." This will make an expression, which you will replace with this:
temp = thisComp.layer("Audio Amplitude").effect("Both Channels")("Slider") * 10;
[position, position + temp]
The 10 after the first line will probably be to much, so adjust it as you need. Now hit spacebar and you'll be set for this step!
Step 3: Head Movement and Motion Tracking.
First go to workspace and choose the option "Motion tracking". Then take all your layers except the video, select them all and right click on the selection. Choose "Pre-compose". This will neaten up your timeline and make all your head-layers one item. now, you will see a new window called "Motion tracking". The motion source should be your video, the track type should be transform, and make sure all 3 checkboxes are checked. The target should be "pre-comp 1". Hit apply, now you're done!