How do I put shelves up on a slanted wall?

It just could not be easier, unless someone does it for you. You just cut a board the same length as the width between those uprights. Furring strip cleats attach to the uprights and you set the shelf on top.

That wire looks like it needs protection.

Maybe something like this will work https://www.homedepot.com/p/ClosetMaid-12-in-D-x-48-in-W-x-12-in-H-Ventilated-Wire-Shelf-Kit-1041/302170942

You could put painted shelves between those stubs, but you would have to add a "bar" of some sort so things wouldn't fall out.

https://www.apartmenttherapy.com/the-2-ikea-solution-for-angled-152501

I agree with Ken, that wire should be in some metal conduit and anchored to the wall to be up to code legally.

as far as shelves goes, you can put in fixed shelves or adjustable shelves depending on what you rather have? Either way you need to start with a small level and draw some level lines on your studs. Start with a tape measure or cut a stick the length you would want from the floor to the height of the shelf as a measuring stick that you can stand on end on the floor and against your stud to draw a line on your setup across the top of your board. Then repeat with your measuring stick on the next stud. Once you got two lines across from each other you’ll want to use a longer level and put the level on both lines on the two studs to make sure their level just in case your floor isn’t perfectly level? Once you know your lines are level in each direction you can put a cleat on each stud by screwing the clear to the stud with sheetrock screws. You can pre drill holes in the cleats to make it easier to screw the cleats to the studs too if you need to?

Adjustable shelves are also pretty easy to do. I would make me a zig out of 1/4“ plywood 96” or the height of the stud at least as high as yo would want your top shelf to be plus a few extra inches if your not going floor to ceiling? Cut your angles on your zig to match the angle of your studs. This is easy to do by putting your zig against your stud and back wall, then take another stick to lay on the floor that’s tall enough to cover the high end of the bottom of the zig and just draw a line across the stick on the zig to get the perfect angle your looking for. Once you got your angle cut you can go off that angle to measure for holes to drill for adjustable shelves or if you have a adjustable protractor you can set it at your angle of the zig and start where you want your lowest shelf to draw a line across your jig. Normally you would drill holes every inch apart but you can drill them apart at any height you choose? 1 1/2 to 2“ apart would work too. You can also drill 5-6 lines of holes then skip 6 inches and start with another 5-6 lines of holes if you don’t want to drill a bunch of holes every inch apart? Once you got all your lines on your jigs where your Shelves will go. You’ll want to measure in on each side of your jig a 1/2 and put a mark there so you have basically a + on your zig where you will want to drill your holes thru your zig for your shelving pins. once zigs are drilled you can put them against your studs and use the zig to drill your holes in your studs for your shelving pins. Note: there are different size and shapes of shelving pins, you can get a metric or standard 1/4“ pin and the pins I prefer to use are a L shape with a pin welded to the L to slip in the holes. You just cut your shelves a 1/4“ shorter so the shelf can sit down on the L of the pins and the shelf keeps the pins from ever coming out this way too! Myself I ‘m big on adjustable shelves cause I never know when I may need my shelves closer or farther apart for what I need on my shelf? With fixed shelves your stuck to whatever that distance between shelves is and if you have something too long you have to put it some place else! Adjustable more work but in the long run a lot more versatile to moving around for whatever you may want to put on your shelves in the future??? As long as your shelves are level things shouldn’t fall off your shelves unless you have a entery door that might get slammed? In that case things could fall off your shelves. To prevent that you can ad a piece of trim on your shelves on the outside edge with a piece of molding something like 1 1/2” x 1/4 x the width of your shelf that you glue and nail on the edge of your shelves to prevent anything from vibrating off the edge of your shelves! I also recommend using 3/4“ thick plywood for your shelving. You can use 1/2”, but it tends to bow easier and 3/4” is just a nicer looking shelf that has plenty of strength to hold heavier items! Hope I’ve not confused you with these directions? It’s actually pretty easy to do, once you’re done it once it be a piece of cake next time! Nice thing about a zig, if you make a mistake you can always start over with a new board to make a new zig! But if you mess up your studs, well that’s another problem!

I think you could just put some cleats on the studs (making sure each side is the same height). You’d have to meiter the ends of the cleats so that they fit flush against the wall. Then after you cut you shelf boards to length, meiter the back side so that it fits to the wall and secure the shelf to the cleats on each side. If you’re worried about that cord, drill a hole in each shelf to thread it through. That will keep it usable and out of the way. Sure hope this helps! 😊

You now have some really good ideas. Don’t get overwhelmed. Just decide if you want your shelves only on the two sides like a ladder, or if you want them going across like a capital A with extra bars. Best wishes 😇