Remove the furniture from the room. Lay out tarps over the floor.
Roll primer over the entire wall with a paint roller. Let it set for 12 to 24 hours.
Spread spackle over a few square feet of the drywall, at one end, using the rubber grout trowel. Spread it on as thick as possible, while keeping it on the wall.
Press the flat bottom of your grout float into the spackle. Pull it straight out, making peaks and bumps in the spackle.
Mover the float over and press it into the flat spackle next to the first textured area. Pull it again, making peaks and bumps. Repeat, texturing the whole spackled area.
Spread on more spackle over the next section of wall. Texture it as before. Repeat and continue, spreading the spackle and texturing it section by section. Let it set for 24 hours before moving the furniture back in.