>>937483108 (OP)2x4 and drywall cut the hole bigger so it's square and even drill the 2x4 when it's behind the wall so you have a support for your patch take your perfectly cut patch and screw it to the 2x4 support so it looks flush and neat then fill any gaps in with spackle. Now take some screen mesh for a window and glue that fucker on tight smooth it out cut it so it's flush and not overlapping the other wall then paint the wall! Or paint the patch if you can color match get all your tools and parts in order before you start! Be patient and cautious
Small sheet of drywall
A drywall saw or razor blade
The shittiest cheapest drill
Some screws that aren't too big don't worry it's gonna hold
Screen meshing that is matching the pattern
Some paint get a small can it's only 1 wall
Brush
A 2x4 that's longer than the hole your gonna make
Glue