The raven method is a very simple-shifting method.
You basically lay down on your back in a starfish position, and you start counting to a hundred, but in between each number, you say affirmations such as "I am shifting," "I will shift," etc.
Once you get to a hundred, you start saying I have shifted, and if you still haven't, I recommend repeatedly counting till you do shift.
If you lose concentration, that is fine. Just make sure to concentrate again. If you feel tingly and your arms and legs feel numb, that is fine because you want your consciousness to be awake while your body falls asleep.
The tingling and itching feeling is your brain figuring out if you are still awake asleep because of your lack of movement.