Don't neglect unused space in your home. If you've got a spare corner, put it to work with a corner closet. You can build one from scratch with some plywood and studs. It's not difficult using some hand tools and a few supplies. The depth of the closet is regulated by how much of the corner you want to use. The height is determined by your needs.
Draw a footprint where you wish to build the closet. Measure out from the corner on both walls and mark the locations on the wall for the depth. Use a stiff piece of cardboard or 1/4-inch plywood to create a template that indicates the sizes for the shelves and overall width and depth of the closet. Begin by placing a square piece of cardboard or plywood on the floor, with the corner of it tight in the corner of the wall. Draw a line across it from the marks you made on the wall and cut along the line. The resulting template is the size and shape of the closet -- its footprint. The template allows you to gauge the size of the closet before you build it. If it needs adjusting, cut it down or make another one.
Measure up the wall for the height of the closet and mark it. Run a stud finder along both walls to locate the studs and mark them. Cut two two-by-fours to the height measurement, use a level and the template to align them vertically and screw them on opposing sides of both walls. Measure up the walls on both sides and divide the measurement into how many shelves or spaces you desire for the closet. Cut studs for both walls and at the top. Measure and cut the studs so that one end of the stud fits into the corner, with the other end butting into the vertical studs on the front. Screw the horizontal shelf studs to the wall. This is the frame of the closet.
Use your template as a guide to cut shelves and for the top of the frame. Test fit the template into the frame. If it doesn't fit perfectly because your frame didn't go together as planned, trim the template as needed to fit, and then used the template to trim the other shelves. Use the template to cut shelves from 3/4-inch particleboard for economy, 3/4-inch hardwood plywood for an exclusive closet, or 3/4-inch laminated particleboard for a slick, finished shelf. Place the shelves inside the frame on the studs when finished, but don't attach them yet. You may need to adjust them later.
Measure and cut a face for the closet using 3/4-inch hardwood plywood. It should span across the frame and meet the wall on both sides. Test fit and trim as needed. Tilt the blade on a table saw to 22.5 degrees and miter both sides of the plywood. This allows the plywood face to fit tightly against the wall on both sides. Fit the plywood face onto the frame. Cut, trim or miter it again if needed until it fits tightly against the shelves, vertical studs and wall. Measure and divide the face into two sections for doors, leaving a 3-inch perimeter on the sides, top, bottom and between the top and bottom door openings. Draw the pattern on the plywood face. Use a jig saw to cut out the two openings. Now screw the shelves to the studs and screw or nail the face directly to the vertical studs. The studs will be at a slight angle to the face; that's OK. Center the nail or screw to penetrate into the studs where they make contact with the face.
Measure the openings and cut 3/4-inch plywood doors 3/4 inch bigger than the openings on all four sides. Sand everything and add stain and lacquer to the doors and face. You don't need to stain and lacquer inside the closet, but you can if you desire. Use your choice of hinges to hang the doors. Add door pulls if desired.