Start with a clean bucket and half fill with clean, cold water.
Scrape round the edges of the bucket to remove any lingering lumps.
You are now ready to go. Using a hawk and a trowel, the easiest way to lay plaster on a wall is to work with gravity - put the plaster on the walls in upward strokes. Don t be tempted to play around with the plaster, getting it smooth. Doing this will draw the moisture to the surface of the plaster and make it a lot more difficult to work with. Wait until the plaster reaches the stage where, with a steel float, you can smooth the surface without removing the plaster.