Most sectionals components are connected with hardware: This prevents the pieces from shifting apart when you sit on it. Look at the hardware, to determine which type it is. Clasp connection hardware is flush with the side of the sectional, and snap connections slide into place underneath.
Clasp Connection Hardware
Carefully lift one piece of the sectional. If the piece of the sectional has the downward facing part of the clasp hardware it will slide out of place and you will be able to lift it up. If it doesn't, it will gently lift the other section. If this happens, lift the other section instead.
Move the section a few feet away. This will prevent the piece of clasp hardware from scratching the other section.
Slowly lower the sectional.
Snap Connection Hardware
Gently pick up the sectional that has the male snap piece. The male piece fits inside the forks of the female piece. This will lift the peg from around the fork's teeth.
Carry the section a few feet from the rest of the couch.
Lower the sectional piece and pivot the forked female end underneath, to hide and protect it.