You don’t beat him. I don’t even know how you could. He is the 6th strongest being in the DC Multiverse.
DC Universe
The Presence
Michael Demiurgos
Lucifer Morninstar
Elaine Belloc (Michael’s daughter)(non-canon)
Cosmic Armour Thought Robot
Superman Prime One Million
Now all 5 of these people above Golden Superman can beat him and anyone that would be at their level in marvel/other comics could. Below are the Marvel characters who i think could possibly beat him.
Marvel Universe
The One Above All
Living Tribunal
God Emperor Doom
Beyonder
Phoenix Force
Superman Prime One Million has “Powers far beyond any power held by any metahuman ever. Powers gleaned from the very edges of time and space”. This guy could very well be Nigh-Omnipotent to Omnipotent.
We can reword that phrase up above with almost any of those synonyms for glean and it will still mean the same thing. He also has met with The Presence twice so he very well could have gleaned some powers from him. We can very well deduce this guy is Nigh-Omnipotent.
This guy might be Nigh-Featless but really how would you even realistically show this guy’s limits or powers for that matter.
Also he weilds a Green Lantern Ring which he can recharge all by himself. A ring that is only limited by imagination, willpower, and knowledge. Superman who has eidetic memory and knows probably a good 20% of all the knowledge in the universe. Green Lantern Rings are said to be the strongest weapons in existance. A mushy squishy regular human Green Lantern is hard enough to take down as is. You can only imagine how hard it would be to defeat someone of Golden Superman’s caliber with a Green Lantern Ring.
“With Superman's body starting to turn into pure energy, he and Lois embrace one final time and he proclaims his love for her once and for all. He gives her his cape as a way to remember him before he leaves and flies into the Sun, seemingly sacrificing himself to save the Earth.” This is All-Star Superman before he became Golden Supes. Golden Supes is a Pure Energy Being which means he lost all his previous weaknesses because he is not Flesh and Blood anymore.
All i’m trying to say is it would be extremely difficult for any being to even fathom how to take down this guy.
P.S. that list i made above probably might not be right as for all we know only The Presence and T.O.A.A. might be the only ones who could beat him.
Not only that but he spent 15,000 years in the sun. All Superman fans know that any time he sundips he always gets exponentially stronger. In fact his powers triples every 15 minutes sundipping. 15 minutes go into 15,000 years 525,600,000 times. That is a ridiculous immeasurable boost to every single power he has.
Lzyxm Lzpkts, 5th dimensional Superman, Helped Superman P.1.M. turn a single piece of DNA inside out through time to revive Lois Lane. Not only that but she was given an immortal indestructable body.
But how i would do it.
Easy. I would just invent a character stronger than him and put him above SPOM in the DC cosmic hierarchy, give him meta 4th wall powers and put him beyond the 5th, hell the 11th dimension, able to bend the plot to his will and annihilate the source wall, make him above multiversal, omniversal, ultra-Omniversal and write him as able to create and destroy multiversal characters on a whim. I’d have him able to copy, borrow and overpower all of the other DC characters like The Presence and give him powers to defeat fictional omnipotents.
I’ll call him, Superman Ultra-Prime One Billion.
Sadly for your champion SPOM doesn’t stand a chance. He’s not at the level where he can casually defeat those on the level of TOAA or Presence with a snap of his fingers. Superman Ultra-Prime One Billion is the pinnacle of cosmic power, he was able to rewrite the entire DC multiverse simply by thinking about it and becoming an abstract of all hope embodied by the ‘Gods beyond the Nexus’, the so called mysterious readership. His own body occasionally emits white-blood celled like Star-sized organisms called The Vanguard. A single vanguard was able to devour a whole hoard of Gentry when it attempted to infiltrate and corrupt Superman Ultra-Prime.
Superman Ultra-Prime One Billion possesses the Source and merge it and Parallax into his ‘Infinity Focals’ within his eyes gaining several hundred thousand times their power. He is a billion trillion million zillion times faster than light (as stated) and moved so fast that even Flash traveling across the universe was frozen still for him. He can create millions of clones of himself which can do the same, all which can regenerate from the quantum level. Ultra-Prime One Billion is capable of thinking a hundred billion quadrillion thoughts a second as when he beat the revived Anti-monitor once reformed into the ‘Omega-Monitor’ created to defeat him. He’s out-prepped Batman who was in the phantom zone and had a billion years to plan to defeat him, and defeated an army of Galactuses coming over from the Marvel Universe (The One Above All also acknowledged Superman Ultra-Prime One Billion is on a completely new level and plane of existence compared to himself, and could wipe him out with a casual thought, and the entire Marvel-verse with it.)
When his evil clone Ultra-Prime Nexus with a million times more power than him attempted to kill him, he merely converted him with a point and then assimilated his power into his own.
SPOB would be little more than a smear on his foot sadly, made into unreality faster than the Flash could blink. He’s so outmatched here it’s actually kind of depressing. But yeah Ultra Prime One Billion could handle Super no problem.