Raku

This symbol is typically only used during attunements. It's not one that Usui used, but it is frequently used now. If it helps you do the attunement then go for it.

I use this symbol during an attunement to help open up the aura and chakras. Kinda like a zipper, or like harnessing the energy in my hands like a cooking spoon to break the water and stir the contents of the soup after putting a bunch of spices in.

I, however, don't just use it for that. To me Raku is also a very grounding energy since it's the power of the Heavens striking you in a way that you can handle. So when I need to ground in the power of the Light, I bring it down through me. And when I need to be stable I actually do it the opposite and bring up the Reiki from the Earth. I tend to do this at the same time and thus I tend to draw from the top down with one zig zag, and from the bottom up with one zig zag, and the bottom and top lines respectively of each single zig zag meet. Down with the left hand, up with the right hand, but you can also, absolutely do it the other way around. I usually don't, but do what feels right for you.

The density of the Reiki in the Earth makes it easier for our physical bodies to hand the Reiki from above. The Reiki energy from the Earth more closely matches our bodies and is more familiar so our bodies are more apt to accept it.

Here is an example of how I tend to do Raku.

Raku - I do this simultaneously
Feel free to use and share
Just give credit where credit is due. ^_^