When working with a specific entity, you would charge the sigil, before trying to evoke/invoke them, right? And when you charge that sigil; at least with me, you charge it with your intent, before evoking the spirit. Can you do this with numbers or an item? Like say the number 7, can someone charge that number with the intent to use it for luck or protection? Also, like a necklace? Or say a toy you had as a kid, can you charge that to help you see the future? Does it have to be a physical thing, or can it be something metaphorical as a number or word? Just wandering.
Also, do you have to draw a sigil out on a piece of paper to charge it, or can you visualize it and charge it? Does it depend on certain spirits?