In a large bowl, mix the masa flour, baking soda, and start with 1 1/2 cups of very warm water. Mix well. If the dough seems too dry, add a little more warm water. It should be like bread dough. Cover the bowl with a towel and let the dough rest for about 30 minutes.
Then work the dough with your hands (you can rub a little of avocado oil or olive oil on your hands). Kneed the dough for several minutes.
Then, take a piece of dough about the size of a golf ball and shape into a ball in the palm of your hands. Then, place the ball on your prepared tortilla press (which means you've taken two pieces of wax paper and lined the press with it!) -- this keeps the press clean and easy to remove the tortillas.
You'll put a drop or two of avocado oil or olive oil on a griddle or large frying pan and fry the tortilla on high heat (don't forget to put the vent on and open a window or your smoke alarm will most likely go off!). Cook on each side for up to 1 minute until just lightly brown.
Keep the cooked tortillas warm in a tortilla warmer until ready to serve. You can also make a huge batch, let them cool completely, and separate each with wax paper and freeze for later.