The frame should be slightly shorter than the space between the floor and ceiling; use pressure-treated lumber for framing members that will be next to bare concrete.
Make sure to space the studs 16" apart on center. This will make it easier to install the 4' x 8' plywood sheets in the next step.
This wall will take a lot of strain as it swings open and closed like a door. Instead of drywall — which will tend to crack at the joints under the stress
Use heavy-duty hinges to attach the swinging wall securely to an existing stud. Shim up the wall slightly before attaching it so the wall won't scrape against the floor as it swings.
Attach a 5" castor to the bottom of the swinging edge of the wall so that it will be concealed when the wall is closed. Position the caster so that the wheel extends lower than the door frame but doesn't quite touch the floor; if the door settles due to heavy storage on the other side, the caster will keep it from scraping.
Note: These homeowners used the swing-out door to conceal hunting equipment — including firearms. Always make sure any firearms are safely secured and out of the reach of children.
Determine the best locations for the shelves mounted on the exposed wall studs. Karl recommends measuring the actual storage containers or other items to get the correct shelf heights.
Cut 2" x 8" lumber into triangles to create shelving brackets to mount on wall studs.
For each bracket, position the bracket on the wall stud and tack into place with a nail gun. With the bracket held in place, drill two holes through the bracket and into the stud. Drive lag screws through those holes.
Note: Make sure to install the brackets level — and level with each other