Start by sanding the entire countertop and backsplash / lip areas to rough the surface up a little and help the paint stick permanently. Then, wipe away any debris and clean the surface with a mild soap and water. Wait for the surface to completely dry before moving onto the next step.
Next, tape off any areas that you don't want the countertop coating to stick to and make sure to cover the floors with something as well, just in case. I used painter's tape around the fridge, the sink, the backsplash, and underneath the countertops. Then, I added a painter's plastic underneath the counter to protect the cabinets below, along with an old sheet on the floor. Better safe than sorry on this one.
Then it's time to paint. I'd recommend starting at the back and working your way forward, so you're not leaning over the paint when it's wet. Start with the backsplash lip and paint a thin layer, as shown in the photo below, working your way to the crevices and then painting about an inch or two on to the counter as well to make it easier for the next step.
Then grab a paint roller and cover the remainder of the counter (top and then sides / edges) with a thin layer of countertop coating, again working your way from the back to the front. You will definitely need to apply more than one coat for this project. But you'll have to wait for each coat to completely dry to the touch before applying another coat.
Once that first layer of paint is completely dry to the touch (somewhere between one hour and two seems to be the sweet spot), add another thin layer of paint to the entire counter and backsplash (if applicable), the same way you did the first time. Then wait for it to dry to the touch again before adding another coat. You'll know you've added enough thin coats when you can no longer see the previous counter color at all and the new counter coating looks solid and even.
Once all the coats are on and you're happy with the finish, remove the painter's tape and let the counters cure for at least 72 hours before using. It will be dry to the touch within hours, but if you put stuff back on the counters too soon, it can cause chipping, etc. So, wait the full 3 days if you can, before using the counters as normal.