So, put lettuce on the bottom bun, and put the burger on top of the lettuce. Assuming there’s cheese on the burger, use that as glue for the red onion slice, followed by a tomato slice. On the top bun, paint on some sauce (ketchup, comeback sauce, etc.) and arrange three pickle slices.
Article source: https://www.huffingtonpost.co.uk/entry/how-to-cook-a-perfect-burger-on-a-grill_uk_630609a0e4b00c150d668580