The Invisibility Spell

Today one of my favourite magical practises, the misnamed invisibility spell: misnamed because you don't actually become invisible (Oh, p-lease, Potter, did you think we couldn't see you?), but rather cast a glamour so that you fade into the background. This is exactly like a glamour for an interview or whatever where you make people see a particular thing, only here the particular thing you're making them see is anything other than you.
Since all acts are magical acts, let's start with the work on this plane: there is no substitute for being nondescript. This is not the occasion to have the pink mohican on show, but think camouflage, and of course the first principle of camouflage is that your appearance should merge into the background. Banksy says you can get away with painting anything in broad daylight if you wear a high-vis vest & have a radio playing. Similarly burglars have been known to wear suits to not be noticed. If you can begin to look like everyone else in the context you are already merging into the background.
You know sometimes when you see someone you know outside of their usual context, you have to double take to recognise them? This spell is made easier if you do it outside of your usual context and make a conscious effort not to look like you normally do.
On a psychic level you are only doing the same as in any glamour, only the idea you are putting in people's heads is something other than you. It is the exact opposite of being one of these people with Presence, who fill a room as soon as they enter it, so the first thing psychically to do is reduce your presence.
Some of the books say you should practice glamours in front of a mirror, but I disagree with this: because a glamour's target is someone else the mirror means you're in danger of seeing it yourself and not the target. Be like actors, darling, & remember that this spell is a performance for an audience. So the rehearsal space should be somewhere that gives you an awareness of other people's presence.
The visualisation you have in your mind must be of your surroundings, & this is the most difficult bit of this spell, since psychically you must not project an image of yourself at all but of 'not-you'. Even that is difficult because as soon as you think 'I am being invisible', you start projecting your invisible presence, which you also do if you start thinking, 'I am not seen', since the word 'not' doesn't seem to work in magic.
The difference between this and other glamours is that you must not try to get an image into the other person's head; if they're a natural empath or in the slightest bit psychic they'll feel your presence. You almost have to close down your psychic awareness to do this, because that is one of the things that creates your presence. It is also the exact opposite of psychic vampirism, where you 'feed' off other people's energy, and also the opposite of shielding where you prevent others from accessing your psyche, rather you are keeping your presence from entering other people's psyches.
You will know you've succeeded at this when other people almost walk through you, and you get this strange sense of isolation in the midst of other people.
I made the mistake when finding the image to use for this post of googling 'Invisible Dick', because I already knew of that book's existence. That awareness prevented me thinking of what else would come up in my search, oh dear. I unwittingly cast an invisibility glamour on myself!
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