What is the most effective way for a magician to open up Portals? (Note for beginners: DO NOT OPEN PORTALS IN YOUR HOUSE!)
Depends where you’re trying to open portals to. One method I learned from my days of traditional witchcraft was performing the compass round. You use your stang and draw the circle on the ground around you counter clockwise. Don’t just draw it though, really use the end of the stang and dig down into the ground. As you do this you would feel the underworld opening up as you yourself descend downwards, meeting the spirits halfway between here and their realm. Simple method that works really well. During and after rituals I could sense legions of the dead in the ritual space. (Note, not the best idea to do this at home but screw it, learn from experience even if it can be a bit dangerous).
So you are supposed to destroy your room if you were to do this at home? Also, how would one go about closing a portal like that?
Nah, not destroy your room. When I did this stuff at home, rather than the woods or a graveyard, I was doing it in the backyard (gave the neighbors some good shows lol). You would close it the same way, move clockwise and feel it closing while you rise up.
So you just move your stang,cane whatever on the floor without destroying it?
Hahahaha… I came here to warn people not to open up portals in your house, or astral temple, but op already thought to add that.
Woods would be the perfect place right?
I had a portal opened in the corner of my living room for nearly a year. It was anchored to my 4 foot wide black mirror.
I didn’t experience anything negative from it. Quite the oppositive. My home was literally flooded with high levels of energy. It was like you were swimming through it.
Of course, I made sure it was guarded and only allowed the energies through that I wanted through. I wouldn’t leave my front door open to the world and say “Hey, ya’ll … come on in whenever you like!”
One of my personal rules is “Don’t do stupid shit.” lol
Pick a spot on the wall to use to scry when summoning a spirit, use repeatedly for same spirit - bam - portal forms. 
Ask them to guard that and keep it stable, do the same for many spirits, before you know it you have a multi-dimensional nexus instead of “jusy” a temple, and all your chums can pop by and contact you, let you know about items of interest, with ease.
@Reaper182
I’m interested in Traditional Witchcraft.
Do you read the Cornish Book of ways?