Please take a seat, a sac of chips and a beer. Try to understand this tut :
1. import a JPG or GIF in Swish
2. draw 4 or 6 or 8 rectangles over the image so the image is totaly covered.
The rectangles may not have a border and has to be one against the other, no space between the rectangles.
3. delete the image
4. group those rectangles as a shape
5. fill the shape with your image (clipped image) (see color fill, linear gradient, radial gradient, clipped image, tiled image...)
6. ungroup the shape again
7. group again those rectangles but not to shape, just as a group
8. go to your timeline and add the explode effect to that group.
9. Done
You have to experiment with that tutorial and you will be able to make stunning effects !