You can use a brass bristle brush to clean SearMagic cooking grids when the grids are hot. When the grids are cold, you can soak them in a Rubbermaid-type container filled with hot water and a grease-cutting dish soap like Dawn, and then scrub with a brass bristle brush or a nylon dish scrubbie.
Every time you use your grill, you can take the grid on the left, flip it over, and move it to the right end of the grill, and slide the other grid(s) over to the left, and then pre-heat the grill for 10 minutes on high. Also, heat the grill to high and let it run for 10 minutes after you finish cooking. This will help to burn off anything that has dripped onto the grids.
There is a wood scraping tool (GGWB5), which is like a large wooden two-tined fork, which is designed to help remove clumps of food, marinades, etc. from between the ridges on the SearMagic cooking grids. There is also a narrow, brass bristle brush (GGWB10) which is designed to fit between the ridges on the SearMagic cooking grids.