Paint your own dramatic sky - Stage 1

Start with your prussion blue, if working in oils use a tiny bit of varnish or turps to loosen the paint.  Using a large brush cover the canvas with the blue - it should have a good, dark covering - try to use brush strokes in different directions.  While wet, apply the light blue along the horizon line and then create a sweeping motion up into the top, left hand corner.  A tiny bit of light blue should be able to do all this.  Try not to mix it in too much (so brush strokes are still visible). Video demo here -