Take your ammonia-based cleaner and thoroughly scrub your countertop. Spray it on the surface and wipe it down with a dry rag to remove any grime, dirt, or loose debris. Getting it clean will prepare it for the repairs that you're about to do, and ensure that nothing ruins your results.
After the counter is one hundred percent clean you're going to want to identify exactly where your cracks are. Inspect the entire space thoroughly and note where any damage is with a marking tool that is easy to wipe off. Having cleaned the counter you may now notice cracks and chips you did not see before.
Take your glue and squirt it into the chips or scratches. Any fast-acting glue, You want to use just enough to fill the area from bottom to top. This will work for any scratch as long as it's smaller than a quarter. Be sure not to get the glue anywhere else on the surface of the counter or to scrape or wipe it up immediately if you do. When the glue dries it will almost certainly have excess, but in this step you're trying to minimize the amount.