Ok in this tutorial I will show you the outline effect you can use on your images.
Two examples of sites that use this effect are
here and
here (I created the last one myself)
1. Start by importing the image you want to use in your movie.
2. Zoom in, or do whatever you want to do to get a good view on the details you want to line (depends on how much detail you want ofcourse)
I put a transparent shape on top of my image (which I removed later ofcourse) to make the contrast a little lower, this way I got a better view on the lines already drawn. Count this as a tip POPCORN
3. Select the bezier or pencil tool

4. Start drawing!! If you want to animate the lines independently, or in groups, think of ways to remember which lines belong to which part. In my example I used a LOT of lines, and after a while I forgot where they belonged to, costed me a lot of time. So name them, group them wahetever.
5. After you're done drawing, decide on how you want to animate your lines.
6. In this example (
link), the lines are animated as if they were drawn. To do this you need to group your lines in sprites and put a mask covering all lines at the bottom of the outline

Animate the mask by adding a move effect. Let it go for example from bottom to top, so it looks as if the starting point for the line is its bottom and it grows from there. Do this in a way that in the end all content is again covered. Repeat these steps until every line is revealed. Let the image fade in afterwards.
7. In this example (
link), the lines are grouped in only one sprite. Add a circle covering all content and align it top left. Set the width and height to 0.1% afterwards and add a move effect. Make it as long as you want and set the width and height again to 100% at the end of the move effect. Repeat this for the image sprite and let this one play after the outline sprite is finished.

Simple as that!
Thank you unholy_gs and josephine for the idea to make this tutorial