To change the order of the vendor columns that you have set up in your vendor template, click Actions -> Edit to the right of your BidTable:
From the Edit BidTable screen, you can change the order of the vendor columns by clicking on the Edit icon on the vendor column to bring up the Edit Column modal:
From there, use the dropdown to select the order in which you'd like the vendor columns to appear:
For more information on creating your BidTable template, please see our Creating a BidTable Template page.