I'm new here and anyone is welcome to tell me to go pound black salt but I very purposefully have designed my practice to be as internal as possible and I work with demons regularly, so I'm hoping I can actually add something. I've had really good luck working with Dantalion, Samigina/Gamigin, and Belphegor following this practice, and I'm currently making contact with Onoskelis (who I'll use as the example). What you need is a sigil, an enn, a number and a pathworking.
Sigil - we all know what a sigil is, all of the goetic demons have one but we don't have to rely on that and can substitute something else if it doesn't exist. EG, Onoskelis is from the testament of solomon rather than being from the ars goetia, and doesn't have a sigil from that text. The folks over at Satania/The Devilist Temple were kind enough to provide one (
) so I used that, but any method you use for sigilizing is valid for creating a demonic sigil. I prefer working with established sigils due to the energy others have poured into them but I've also made my own up in the past.
Enn - a chant to be repeated in order to summon or recognize a demon. These are more from the S Connolly demonolatry canon than they are from the goetic demonology workings. Again, not every spirit has one, same rules apply for enns as for sigils. If you can't find one, create one.
Number - a number associated with that particular demon. It can be something traditionally known, it can be arrived at experientially or it can be just made up whole cloth. It's used to determine the appropriate number of repetitions of the enn in order to get ahold of the demon.
Pathworking - a series of visualizations that work as evocation. See Rose's "Lucifer and the Hidden Demons" or Hargrove's "Goetia Pathworking" for a series of pathworkings related to the goetic demons. There are also angelic pathworkings, and I presume any entity you'd care to work with can provide you with one if you work with it. They tend to be of the format something you see, something you hear, something you smell, and then something you see again. Here's an example of the Dantalion pathworking from Goetia Pathworking (from memory, it may not match the text but it gets the duke's attention and that's what matters):
A copper wall lit by candle light
The smell of burning hair
A deep buzzing noise directly behind you
An orange morning sky gives way to a yellow sunrise
Much like the sigil and the enn, I prefer sources other people have used where possible but it's not strictly necessary
You can begin with nothing but the entity's name. It's a repeated process, just silently mediate on the parts you have and wait for the rest to be revealed to you. It might just be the name and a vague description, in which case you'll start by just asking to make contact and get more information. That's how it started with me and Onoskelis. I just had what was in the testament. Some googling eventually led me to the devilists, which is where I got the sigil and enn. Then in reading I found she claimed to be ruled by the moon and made of Saturn. Knowing what I do of planetary magick, I know that in the Chaldean numerology those are the first and seventh planets, so I took that to mean they should be added together to make 8. So now I just need the pathworking, which I'm still gathering, but a typical experience in trying to make contact with Onoskelis would be sitting down quietly and visualizing the sigil while I chant the enn the prescribed number of times (48, as in 8 because that's Onoskelis's number as revealed to me times 6 to acknowledge the Satanic influence and to separate from my angelic workings that follow a similar structure but are multiplied by 3), then I spend a little time imagining each step of the pathworking until I feel the presence of the spirit. When I want to actually ask something of them and need a more intense experience I'll pull in some of the more shamanic elements of my practice (physical ordeals, flow/drumming, recreational organic chemistry, hyperventilation/hyperoxia, things like that) but I've made good contact just lying in bed and working through the steps: visualize the sigil, chant the enn to the number and then work the path. I'm confident Onoskelis will reveal a pathworking to me in time. They all have.
The practical upshot of all of this is deep working with various spirits in a way that can be entirely contained within your head if necessary. I designed the practice while living at home but now I just sorta find it convenient to do this way (though sometimes I do indulge myself and do the whole chalk and salt on the floor, candles and incense and chanting in Latin thing).
caveat: this is a relationship, not a cookbook. If the entity you're working with tells you that any of the above pieces of information are wrong, then they simply are, even if they work for other people. I can't tell you what to do, I can only tell you what I do and how well it did or didn't work. Good luck!
