Using the floating corner method for completing a drywall corner is not the preferred way to accomplish the task, but it can be done very easily by anybody that has a little patience and some basic tools.
Step one: Hang the Solid Drywall
Before hanging the piece of drywall that will be floated, make sure that the solid piece is hung, giving the floating piece a little more stability.
Step 2: Hang the Floating Drywall
Hang the floating drywall as you would any other sheet, using screws and securing it to all of the existing studs.
Step 3: Tape and Mud
Tape the seam by pressing the middle of the tape into the crack, ensuring that half of the tape is on one side, and the other half is on the other sheet. Fill the joint with mud. Using a corner trowel to smooth the mud out, taking care not to push too hard on the floating piece.
After the mud dries the floating piece of drywall will be secured to the dried mud, to the solid piece of drywall. This will make the floating piece as solid as possible while allowing for the drywall corners to look done in a professional manner.