I had posted this a while back on another site, and thought I would share it here. It's a technique I use often with clients. It involves invoking a compassionate spirit into your own body to let them work through you - I do this with power animals and plant spirits, but I think you could do it with any spirit you felt safe letting into your body. I would at least stick with spirits you know well and trust - at least at first. I have only tried this with power animals and plants, but I think it would work with deities or angels or other spirits too.... (the archangels of the 4 directions could be a good option)
I originally learned this from one of my teachers who uses shamanic style methods of trance work. I think you could alter the method easily, but it might be easiest to do while in a trance.
Before I started the practice, I asked my guides which spirit I should work with for this type of work (whatever your goal is for the ritual). One spirit I do this with quite often, and we usually work together for extraction type work. I sometimes use this for other purposes, but that is the most common one.
This is how I do it:
Call in the directions/winds
Make a prayer/state intent
Then I sing a song or two to get me in the mood, raise my energy, and also start connecting with the spirits. I think you could easily insert passionate prayer or a conjuration for this instead of singing.
Then I either drum, or rattle, or just dance and sing myself into a frenzy. You could do it without this percussion, but I use the percussion to help me enter a trance (often I have my fiance drum for me while I rattle). I also use the rattles quite often during the trance for breaking up energy, so they double as a magical tool and trance aid. I will usually chant and sway while rattling to enter a good trance - holding the intention now, that I am merging with my power animal.
Eventually, the spirit is connected to you deeply enough to work through you. Your arms may look like the spirits arms (or claws or wings ect in case of power animals), and you may make strange sounds or speak words you dont know (I make animal sounds sometimes from nowhere, or sing a song I've never heard before). Do whatever work you came to do, and then after, tell the spirit you are done, and let them fade away as you calm down from the trance and also ground yourself in some way (wiggle around, feel your body again, eat ect).
If you want, you could banish at this point. I dont banish with these types of spirits, because they only help me, but if I tried this with a different type of spirit, maybe I would banish.
Types of work you can do with this method:
-See illness or misplaced energy in someones body
-See astral/spirit world around you through your eyes
-Perform Extraction type work or even exorcisms
-Learn to use new magical tools
-Communicate with the spirit, or with other nearby spirits
For protection, while you are merged with the spirit, it protects you. This is why I do extraction work this way - the energy I am pulling out doesnt ever touch me, because the spirit is the one doing the work. It provides a powerful shield. Also, the spirit usually knows what to do better then I do, as extraction is their specialty, so it also allows their expertise to be used fully. My teacher told me you know when you are fully merged, because there is no fear in you any longer - if you have any fear, it means you need to keep merging/connecting with the spirit and enter a deeper trance. Once you are fully merged, you are filled with the power of that spirit (power-full), and protected.
For using a magical tool, I will ask a spirit to merge with me to teach me about the tool. This allows any spirit with expertise with that tool to volunteer. My same power animal merges with me for things like this, because so far, I have only done this with a few tools, and the tools were predominately for extraction work (phurba, feather wing/fan, bronze asian/shaman mirrors, certain crystals and other objects - that's what I've tried so far). I will go through the same process of merging with the spirit, then once merged, they will pick up the tool and just start using it. This is how I learned to use a number of my magical tools.
You could get really creative with this - there are all kinds of possibilities!