You can find a plethora of personal cleansing techniques on the web and in various New Age/Metaphysical books and most of them will work for most people. However, for those of us who do a lot of shadow work the gentle garden variety cleansing can be a bit too gentle. There are many cleansings that go along the lines of "step into the shower and visualize the water washing away your negativity/stagnant energy/unwanted trait/etc. and the black ooze of this flowing off your body and down into the drain." For an everyday cleansing that sort of thing is great, but it isn't always enough. Those sorts of cleansings area bit like vacuuming the carpet - it takes care of dust and a bit of grit, but does nothing for set in stains. That requires something a bit stronger.
I recently performed the Order of Scathach Armouring Ritual which included a self-cleansing. In that ritual you write down a list of traits of which you would like to be freed and then burn the list to banish them. Before performing that ritual you do about six months of work. After six months of introspection I was pretty much rid of the surface level grit that such a simple cleansing could effectively get rid of. So I had to ramp things up a bit in order to feel really cleansed. In the ritual you need a physical fire to burn your paper and I did this as step one of the process. Then I closed my eyes and went to my astral temple (a sacred space in the astral plane that I can go to mentally and energetically to do workings that I don't want to do physically - very useful when your mental work would be dangerous if carried out physically).
At my astral temple I called the spirits of fire to be present and to aid me. They showed up in the form of a large magickal bonfire directly in front of me. I asked the spirits of the fire to help me burn out the things I was having the most trouble with (self-doubt and fear). I then, astrally, stepped into the fire and let the flame burn. As the flames burn my clothes and skin I visualized all of my ingrained fears and doubts burning away. I stayed in the fire until it seared through my bones and reduced all but the best parts of me to ash. All that was left was the etheric body in its purest form. As I stepped out of the flames my physical body regenerated without the old patterns. I thanked the fire for its help and watched it depart. I then returned to my physical body and completed my ritual.
This type of intense visualization is a very effective way of giving magickal workings extra oomph. It's not the sort of thing that anyone in their right mind would ever do physically - it would kill you. But doing this sort of thing mentally sends a definite message to your subconscious and will generate much more powerful energy than your average rite. It's not for everyone, most people don't want to dig so deeply to root out the source of their problems - particularly when they "are" the problem.
This sort of work should only be done after months of prep, working through the cycle of cleansing and realization gradually. Every time you cleanse yourself of one kind of negativity it allows you to see the negativity underneath, you get rid of that and see what was below that, and so on forever. This sort of work is never finished, but as you do it the process becomes its own reward. With each layer of myself that I cleanse and purify I find myself become a stronger, kinder, wiser person. It can be really hard to look at the components that have caused me problems over the year and harder still to see what I did to make it worse, but facing it sets me free. Self-examination is hard work, but we owe it to ourselves to undertake it and become the best we can be.
Suggested ebooks:Susan Greenwood - The Nature Of Magic An Anthropology Of Consciousness
Peter De Abano - Heptameron Or Magical Elements
Aubrey Bell - The Magic Of Spain