Mix dough. Combine masa harina, water, and salt in a large bowl. Mix with your hands to make sure it the dough is thoroughly moist. Knead for a few minutes to incorporate the water into the flour.

If it is too wet, add more flour, if it is too dry, add more water. You want the dough to be soft, but not sticky. If it cracks when you try to roll a ball of dough, add more water and mix again. 

Cover with plastic wrap while you prepare the press and pan. 

Prepare the tortilla press. Line the tortilla press with plastic. A plastic produce bag from the grocery store works great. Cut the produce bag into two pieces that are the same size as your press. A resealable plastic bag also works but I find it to be a little too thick. 

Heat pan. Place a dry comal, cast iron skillet, or non-stick frying pan over medium-high heat. 

Roll dough into balls. Form a walnut-sized piece of dough into a ball. Start with this size and work your way up to a larger piece of dough which will make a larger tortilla. 

Press dough into tortillas. Place dough in the middle of the tortilla press on top of the plastic. Cover with second piece of plastic then close the tortilla press gently. Press down, lift the top of the press, flip the tortilla and press again. Repeat as many times as needed to make a 1/4-inch to 1/8-inch thick tortilla. 

Gently lift the lid of the tortilla press. Lift the top piece of plastic off the tortilla. Flip tortilla onto your left hand and then remove plastic from the bottom. Half of the tortilla should be on your hand with the other half hanging off. This is the part you'll put on the comal first. 

Cook tortillas. Carefully but swiftly flip tortilla onto the hot comal. Don’t touch! Let cook for 15-30 seconds or until the tortilla begins to peel off the comal.  Flip with a metal spatula and cook on other side for 15-30 seconds. Flip again, cooking another 15-30 seconds. Ideally the tortilla will begin to puff up, if not, don't worry, it will still taste delicious. Flip one more time cooking a final 15-30 seconds.  

Remove to tortilla warmer and repeat with remaining dough.