How are you mounting the projector? Just putting on a shelf or hanging from ceiling?

If you're hanging from ceiling then you need to buy a projector mount and will probably need help to install the mount.

Other installation issues:
- deciding how far you want to put the projector
- deciding what height to put the projector
- adjusting the zoom to fit the image to the screen
- adjusting focus to get it sharp

For mounting, there are 3 dimensions to consider:

1. Centering between left and right - try to get it in the center of the screen. Doesn't have to be precise because you can use the lens shift to move the image. But don't use too much lens shift, so as far as possible get it mounted in the center.

2. Distance from screen - your projector has zoom, hence you can play around with the distance. From the specs you mentioned, seems can get a 100" screen anywhere from 3072mm to 4664mm distance.

3. Drop distance from ceiling - some people recommend that your projector be at least within the top border of your screen. You can use the lens shift to move the image, but again don't use too much lens shift.