Opening up, modifying, or entirely removing one or more walls is relatively easy but guaranteed to make a mess. In addition, you must patch the floor, walls, and ceiling.
Before you remove any wall studs, you must determine whether or not the wall is a bearing wall—part of your home’s structural system. (For more about wall structure, including how to build a non-bearing wall, see How to Build an Interior Wall.)
Be aware that plumbing, wiring, or other mechanical equipment within a wall can make removal far more involved. Rerouting plumbing, in particular, can add significantly to the work.
To prepare for demolition, mask off the area with plastic sheeting to prevent the dust from permeating your home, and protect the floor with drop cloths. Turn off the electrical circuits that supply power to receptacles, light switches, and wires in the wall. Pry off any moldings.
To remove gypsum wallboard (drywall), punch through the center of the panel with a hammer and use a prybar to extract the pieces. To dispose of plaster and lath, smash the plaster with a sledge hammer and then pry off the lath.