Take all furniture out of the room. Lay down tarps.
Clean the wall thoroughly with household cleanser and a sponge, getting off all dirt and debris. Let it dry for 24 hours.
Use a paintbrush to apply primer around the edges of the wall, "cutting in" around the perimeter where it meets the surrounding walls, ceiling, floor, doors and windows. Use your paint roller apply the primer over the rest of the wall.
Brush textured paint along one edge of the wall, working along the whole side. Expand out from there with the roller. Step back after every few square feet of coverage and assess it, from a distance, making sure the texture is consistent.
Continue applying the textured paint across the whole wall, brushing it on around the edges and using the roller on the flat spans. Stop frequently to assess the consistency of it, especially when you paint over the areas that have spackle on them. Cover the whole wall.
Let it dry for 24 hours before moving the furniture back in.