The steps are i the photos, i have highlighted the parts you need to add.
Step 1: The Pieces.
Step 2: Main Part.
Step 3: The Bridges.
Step 4: The Spires.
See how to attach them on step 6.
Step 5: The Outer Ring.
Step 6: Attaching the Spires.
Step 7: The Base.
Step 8: Done!
This was a difficult to design and build, but I'm happy with the results. (also had trouble finding bricks.) hope you like it! :)
Have fun and enjoy your new space station!