Make a checklist. Keep all ingredients and other items for frying within reach.

Slightly fry the flours in a kadai (vaanali in Tamil) with butter about 2 min. I use a cast iron vaanali over medium heat. Dry fry sesame seeds, powder it in a coffee blender, add to the flour. Add baking soda, asafetida, sukku and cumin powder, mix them.. Salt to taste. Add water (3-4 cups), little by little to make the soft silky pliable dough.

Heat oil (vegetable oil), no refined oil please) over medium high flame. Never use high flame. Just drop a pinch of dough in the oil to make sure it is hot enough, when the heat is right the dough will surface on the oil. If oil is not hot enough murukku will not be crisp.
Grease the inside of achu (murukku maker). Fill up ¾ of it with the dough.. Here you have a choice. You can directly press the achu /mold over hot oil to make murukkus of desirable size.

Or alternatively, you can grease a jalli Karandi (Tamil, it has holes for oil to drain. see the image). Make the murukku over it, and then place it in oil. Murukku will slide into the oil. You will see bubbles in oil while frying. After a couple of minutes, turn over. While frying, using the Karandi (slotted spoon) rotate murukku inside the oil for even frying when bubbles subside, murukku is ready to lift. Lift it with a slotted spoon, drain the oil. The whole process may take about 5-6 minute

Drain excess oil from murukku on a paper towel.
Let murukkus cool to room temperature. Aromatic, flavorful, tasty crispy muruku is ready to eat, Wow!!! It simply melts into your mouth. You can store deep fried crispy murukkus in an air tight container at room temperature over a week or so.
This recipe will give about 10-15 murukkus depending on the size. the image below sums up the whole process.