Dear Bro,
Did you got the user manual picture. Kindly go through it. Step wise:
1. Take big clamp as ur no.2 picture shown
2. It have 4 holes
3. Screw it to dish back side. Means first work complete.
4. Then make the stand - Wall mount: Drill and tie big screws.
5. 2 supporting arms also drill in the wall
6. Then join the pipe with dish with angle clip.
7. Extra screw may be for side support lnb arms