The Self-Discovery Phase
Potentially, the most challenging element to the Technique is finding and knowing where the spot that correlates to your inner clitoris is. Because you never see this as a physical location with your sense of sight, and you can't directly touch this area either, then everything depends on perceiving this location as a matter of sensation. Only your own internal awareness can accurately identify where your spot is. For every new partner, you will need to find the adjustment that achieves pressure against this spot given his characteristics.
The Forward Wall ♀
As a matter of ensuring focus on the correct region of the vaginal canal, here is a quick exercise that you can either try for yourself or follow along as a concept. Let's say you are in the process of inserting a new tampon with a typical applicator. Normally, you would insert the tampon until a certain depth and then compress the applicator in such a way that it collapses and this causes the cotton part of the tampon to be a free moving object that will absorb the menstrual fluid. Given that sequence of typical events, for this exercise, pause the activity after having inserted the tampon and before collapsing the applicator. Before collapsing the applicator, you will take this opportunity to use the tampon applicator to cause a touch to a certain region of your vaginal canal. For a moment, remove your hand from the tampon applicator so that it is in the state of having been inserted in your vaginal canal but not collapsed yet. Then use just your index finger and thumb to grab the end of the applicator where the string is coming out and move the string end of the tampon applicator just a slight distance towards the backwards direction, towards your tailbone. This will cause the tampon applicator to pivot at your vaginal opening and the end of the applicator with the cotton material will move in the forward direction. This action causes the cotton material end of the tampon applicator to move in the direction of the "forward wall of your vaginal canal". Take a moment to notice this area of your vaginal canal. This is the region of your vaginal canal where your spot is. It is the region of your vaginal canal that is adjacent to your inner clitoris. It is important to know this area in order to be able to cause the stimulation needed for the Technique.
Experimentation ♀
Now that you have a general idea of what is meant by the "forward wall of your vaginal canal", you will eventually need to train yourself on what it will take to get alignment between the "male implement in the inspired state" and your spot. And now that you have developed an understanding of the correct direction, it will next become a matter of finding the right angle and the right depth combination and choosing a position on your partner that facilitates everything, probably that will mean you are on top of him. A recommendation for this phase is having a starting set up that allows you range of motion to test different depths and angles. For me, I had my accidental discovery moment during the first time I tried out chair sex. You will have success when you feel the pressure and just how sensitive your spot really is.
Here is another helpful hint for your actual experimentation practice with your partner. As you are testing different depth and angle combinations, keep your index finger on your outer clitoris. Then you will be involving more of your body to help you ascertain positionally where everything is in relation to one another. This will help you guide yourself so that the overall objective is to connect the index finger to the outer clitoris which is connected to the inner clitoris which you are trying to connect to with the head of the "male implement in the inspired state". By connecting these various parts of your body and including more of your physical body in the pursuit, you are giving your internal sense of position more area to refer to.
Once you've found your spot, and probably after a few instances of success with the Technique, your muscle memory will take over and knowing your spot and what it takes to get the alignment will just flow more naturally for you.