This is how my mother-in-law taught me to make tortillas.

I'm guessing at the measurements, since the only thing I measure is the flour Mix the flour and sal. Mix in the crisco with your hands till it is the texture of small peas. Add the hot water a little at a time till you have a soft elasticy ball. Knead still shiny and smooth. Let rest for 10-15 minutes. Make 8-9 small balls. Roll each ball into tortilla and cook on Hot well seasoned cast iron skillet. Flip when side is golden. They should bubble if you have done it right. Keep in tortillas warm in a towel.

Tips: I use a broom handle to roll the tortillas. For some reason a regular rolling pin just doesn't work well. Roll out what you plan on using. Keep the remaining balls in a plastic bag and paper towel in the fridge. I have never had good luck cooking them on anything but cast iron. Don't flip them till they are cooked on that side and don't worry about a few burned spots, it adds flavor.