How is it done? Is it as simple as drawing a banishing ritual and giving license to depart?
A portal is not a spirit presence, so thereās no point telling to to go anywhere. Close it the same way you opened it, in reverse, or visualise the gate/portal closing down, like a door shutting, or a camera iris spiraling shut, or stitch it shut, or state aloud āthis portal is closedā and know it is closed by your will, whatever works.
After sobering up and reading your response to him, I think you understood him better.
how does something so simple work? how do they open? i feel i do it intrusively on accident in my house
Depends on the kind of portal, but the mage created ones as the OP referred to are weak and a matter of will.
Naturally occurring ones can be very strong, and may be geomantic in origin, which is to say geomagnetic. They can be formed from underground water flows, caves and piezoelectric rock formations, probably other things. Those you just cope with, and ideally donāt sleep over them, they can mess your your energy and give you cancers and such, cause poltergeist activity, forms parts of ley lines aka fairy roads etc., theyāre not that great to have in a house.
If you have something like this put a large something made of cast iron between it and you. Iron is magnetically active, it attracts magnetic fields and disrupts the flow. This is the principle behind why iron horseshoes over lintels work to ward off ābad luckā and why the Fae are supposed to hate iron. Itās more physics than magic codified in legend.
Doesnāt actually matter what the object is, it can be a frying pan if you like, railroad spikes and coffin nails are romantically popular. Putting it under your chest area where you sleep is an old remedy for warding off night hag attacks.
Iāve only recently actually realized how powerful those portals have been that weāve all been opening all these years as practitioners of ceremonial magick.
We have shaped and molded the entire planetary sphere.
We have literally caused everything thatās happening right now, and maybe not so directly as one might believe.
What Iām trying to say is that weāre programming our shared reality in stages.
I do apologize if this was too off topic.