I don’t think it matters what technique you use as long as you put the energy into to it as the method is designed, and yes that might take some practice to get the skill down.
Your attention tells the energy where to go: and that’s inherent in the technique, then, your intention is going to tell that energy what to do when it gets there.
So if you give it fuzzy instructions with fuzzy intention you will get fuzzy results, that’s why it’s so important. Analogy: If you want to drink a glass of water, you make it so it goes only in your mouth: you don’t splash it in your face.
Try this energy building exercise, then face your palms together an put your mind in the center of each palm until they tingle. Then move your palms in and out and see if you can feel anything like magnetism between them. When you can do that, put one palm and move it over the crystals, and see how the feeling changes. If you leave you palm stationary over it, you will start to charge it. If you intentionally see energy flowing from your palm into the stone, you will charge it faster.