Here is a small patrol of Tau models, some of which have already featured on this site. They are displayed at home on my gaming boards.
The boards are made from 2' x 4' MDF boards from B&Q. I paint the board with a mixture of cheap white emulsion paint and fine sand to give it a textured undercoat. Next I spray it black (get a big can of black spray from B&Q, its much cheaper than using GW spray). Once the black coat has dried I dry-brush with several increasing lighter shades of brown.
You can take your GW paints down to B&Q and have them mix up a tin of waterbased emulsion to match most colours. £10 will get you a liter tin, which goes a long way and is much cheaper than trying to do it with GW's own.
The hills are made from 1" deep layers of polystyrene packing material, based on thin hardboard cut to shape with a jigsaw. Anywhere between 4mm and 6mm is good for basing. I bevel the edge of the base using a dremel with sanding pad. The polystyrene edges are rounded off using fine grade sandpaper. Once the hill is built I paint it with paint/sand mix, spray it black and dry-brush as for the boards.
Make sure the paint/sand mix covers the polystyrene well, or you will end up with melted polystyrene when the spray hits it. This can be quite a useful effect for rockfaces and battle-damaged areas but you need to control it and make sure it only happens in the areas you want.
Once the drybrushing is dry you can add patches of flock here and there to add variation. If you want to add different textures to the board surface you can glue on patches of heavier sand or gravel in places prior to the black spray stage but after the initial paint/sand coat. If you choose to do this be aware that these patches might mean that other placed terrain features don't always sit perfectly flat on the boards.
