I think there area a few threads on this. Try the search function.
Cold will slow reactions. So if you know you won't finish before you open, best is to pour immediately into a smaller container, like a half-bottle, seal that and put it in the fridge. Then drink the rest. Vacuum is kind of useless - you don't create a vacuum anyway.
Or you can buy a Coravin or something that injects Argon into the head space. That should work for a few days. I'd still put it into the fridge.