Use Side Wall Brackets (974) where you have available side walls to fix onto.
If you have 'Open Ends' you can use Shelf Support Brackets (1164/1166) instead. If supporting three or more shelves you can opt for a Shelf Support Pole (1009).
You will need to add a 'mid-support' every 91cm/3' along the length of the shelf. This can be Shelf Support Brackets (1164/1166) or Shelf Support Poles (1009) if making a stack of shelves.
Corner Supports (120) are required when 'Butt Fitting' shelves at a corner. Don't forget to order a Shelf Support Bracket for each corner as well.