There is no "correct" spin-rate, distance from the body or diameter of the chakra "mouth" -- Trust your intuition.
To explain a little: Starting with the first chakra, I breathe in slowly through my nose and mentally "stir" its funnel-mouth quickly clockwise with a mental finger while visualizing my aura filling and being infused with bright red.
Breathing out through my mouth, I pour any "excess" red out into the world around me. I continue on the first chakra until I feel my aura is red enough (subjective, I know). I then move up to my second chakra, stir both aspects quickly as I breathe in and fill my aura with a good, solid orange, adding it to the red of the first chakra, then breathe any excess color out through my mouth. And so on up through the white/lavender of my seventh chakra.
I then visualize that I achieve a sense of mental balance, holding each and all chakras in their open, spinning, colorful state, my aura suffused with all the colors, and slowly open my eyes and look out on my surroundings through this heightened state of calm.
I find that my posture improves during and after these exercises and for awhile afterwards, and with deliberation and balance, I then move on to my next chosen task.
Locating the Chakras and the colors to use :
1.) Red: Straight down between the genitals and the anus w/ only a single aspect.
2.) Orange: Midway between the top of the hip bones w/ front and rear aspects.
3.) Yellow: Just below the sternum over the diaphragm w/ front and rear aspects.
4.) Green: Between the breasts w/ front and rear aspects.
5.) Blue: Just above the junction of the collarbones w/ front and rear aspects.
6.) Purple: Above the line of the eyebrows ("third eye") w/ front and rear aspects.
7.) White/lavender : Straight up out of the top of the head w/ only a single aspect.
