I wanted to make a kitchen shelf that was bulky without all of the brackets or hardware that comes with it, so I decided I was going to make floating shelves in our tiny NYC apartment. The challenge of this project was not only building a floating shelf with a corner built into but also I had to make it sturdy enough to hold heavy-duty kitchen equipment. I was surprised at the amount of prep work but it totally paid off.
Because of the corner built into the shelf, there were two segments of the main support, each a different size (see photos). The key to both of these was to find studs, especially if these shelves are supporting a fair amount of weight. I made sure to drill 2x 3.5" screws into each strip. Then all I had to do was mount wall anchors for the screws NOT going into studs behind the wall.
I used a Ryobi table saw to cut the "L" shape into the Birch plywood and a miter saw to cut the bevels into the Red Oak side boards. Helpful hint: It's way easier to have two people for the table saw since it stops midway!
After the pieces were cut, I laid down a strip of glue and used the Ryobi AirStrike Brad Nailer (that thing is amazing!) I let it set over night and stained with a medium stain from Miniwax. After attaching the supports, the main shelves fit over them like a sleeve. I laid down some strips of glue (lightly, don't go heavy) and used the cordless Ryobi Nailer to set everything in place. The main supports hold the weight perfectly and the Brad nails + glue makes sure these shelves are not going anywhere!