How do you go from no faith, to a little faith, to tremendous mountain moving faith? You do it one day at a time. Just as you have learned anything in your life. You had to learn it one bite, one piece, one letter, one number, one step, one recipe at a time. That is also how you must increase your faith.
You must learn to fully trust in His power. Once you fully trust in Him, believing will come naturally. Train your mind and the rest will follow. One day at a time is all you need to start. God will do the rest. Trust and believe. He is the same today, as He was yesterday.