Grind setting is not the "coarse" setting on the grinder. Rather, halfway between this setting and the "drip" setting is where you should be. Depending on which grind setting you use, you will keep water in contact with the grounds for a total time of between 4 and 6 minutes. You will need to determine what the contact time should be based on how the brew tastes. If the coffee is weak or watery, you will need to increase the contact time. If the coffee is too strong or bitter, you will need to decrease contact time. So, start with a 5 minute contact time and go from there.
The simplest and most effective way to brew using a press pot is to first pre-heat the pot and plunger with hot water. Discard this water after the pot is very hot. Start the timer as you pour the first bit of water over grounds. Fill the pot 1/3 full and swirl well to ensure all grounds are thoroughly wet. As the timer reaches 40 seconds, slowly continue to fill the pot while swirling (this swirling will knock down the foam/bloom that builds up). Do not fill any higher than the bottom of the pour spout on the pot. Gently rest the plunger in the pot (so the screen of the plunger is not making contact with the grounds). Slowly press, but do not force, the plunger down onto the bed of grounds as you near the bottom. Serve the coffee promptly.