This is what I started with -- a huge blank wall. I needed more storage and more light, because this is a my craft room.
So we bought a floating shelf (IKEA LACK) and some LED under-cabinet lighting. I used these lights: https://amzn.to/2qlvRye (affiliate ink)
For this idea to work, you'd ideally want LED lighting with white cords. Sure, you could use stick-on LED lighting, but it'll drive you nuts when the batteries keep running out -- so go with corded lights!
Measure 1.5" from the front edge of the underside of your shelf and place the sticky velcro pad that comes with your lights here. You'll want to space your lights out equally too, of course.
Now drill a hole right behind the sticky pad. We use a 1/2 drill bit and we went all the way through the shelf to the other side.
Push the end of the LED light cord through the hole, from the bottom of the shelf to the top.
If you need help pulling the cord through, use blunt scissors or tweezers.
Attach the other side of the sticky velcro pad to the underside of your LED light.
Attach your LED light to the shelf by pushing the two pads together.
Here is the LED puck light installed on the underside of the shelf. Note the position of the hole and how the cord goes through it.
Here all of the LED lights installed on the underside of our shelf!
When you turn your shelf over, you'll have a mess of cables. So tape them down with clear packing tape so they are neat and organized.
Here are the cords all tapes down nice and neat on the top of the shelf.
Now connect all of your LED cords to the cord box.
Now that your shelf has its lights installed, it's time to put your shelf up on the wall. Find the spot you want to mount it (we put ours about 12" from the ceiling) and mark the center.
Now install your shelf bracket onto your wall -- be sure it's level! Once the bracket hardware is up, you simply slide your shelf onto the bracket.
And here is the completed shelf with the under shelf lighting. It's SUCH a great thing to have!
Keep in mind these floating shelves don't hold a lot of weight, so I recommend you only store lightweight items up here. I use this shelf to store my paper flowers.