Cut a ziploc bag open along the sides. Open the tortilla press and lay the opened bag on top and bottom.
In a large bowl, mix together the masa harina and salt. Pour in the water and stir to combine. Knead the dough with your hands in the bowl for 1-2 minutes, or until it is smooth and no longer sticky.
Pinch off some dough to form a golf ball size ball. You should get about 18-20.
Place 1 ball between the cut ziploc and press down until the dough has spread about 6 inches and ⅛ inch thick.
Heat a skillet over medium-high heat. Add freshly pressed tortilla and cook for about 1 minute before flipping and cooking another minute.
Stack the tortillas in a clean kitchen towel so they seam and finish cooking. Repeat with remaining dough.
Notes
If the dough is dry and crumbles, add more water in 1 tablespoon increments. If it is too wet, then add masa in 1 tablespoon increments.
Use a ziploc bag instead of plastic wrap so the tortilla won't stick.