Summarize this article in one sentence.
Set each piece of your new granite countertops in place one at a time. Make sure each piece is set correctly and is positioned flush against the wall. Granite can be extremely heavy, so have a friend or 2 assist you in lifting and placing each countertop piece. Once all of the pieces are in place, you'll likely notice that there are gaps or places where the countertop isn't sitting level. To fix this, place small plastic shims between the top of the cabinet and the bottom of the granite. Check multiple places with a level to make sure your countertop is perfectly flat. Lift up or take off the granite pieces. Squirt half dollar-sized dollops of silicone sealant onto the top of the cabinets every 68 inches (1520cm) all over the entire surface. Then, lay the pieces back down one by one and adjust them as needed to ensure that they're properly positioned. Check with a level halfway through the silicone's drying time to make sure your countertops haven't drifted. Wipe the countertop down with a clean cloth and a mixture of warm water and dishwashing liquid. Dry the counter completely with another clean cloth. Then, saturate the surface of the countertop with a sealant. Let the product sit for 10 minutes, or as long as the product instructs, and wipe the excess off with a clean cloth.

Summary:
Set the granite in place. Use shims to level the counter. Glue the counter down with silicone sealant. Clean and seal the countertops.