To install a double pocket door, ensure that the wall is suitable for the installation, and cut the drywall to make the pockets for the doors. Install the stud for attaching the header, and affix the channel runners to the floor. Fix the floor brackets, and mount the door.
Ensure that the wall where the pocket door is to be installed is not a structural one and contains no wires or plumbing behind it. If the wall is a load-bearing one, a lintel installation over the wall gaps becomes necessary.
Then, cut the drywall for both the doors using a reciprocating saw. Cut between the wall and the studs, take the partition header out and hack the studs down to create the door pockets. Affix a new stud of the right size, and secure it appropriately to the header and the floor.
Fix channel runners of a suitable size to the floor. Verify that the channel is leveled to allow for smooth functioning of the doors. Attach the floor brackets to the metal plate, and mount the wheeled portion of the doors into the tracks.
Ensure that both the doors close flush with each other. Finally, attach the drywall using an adhesive and screws, plaster it and finish using a suitable wall covering.