Hi There,
Been doing dioramas for years and this is the method I use
Baseboard MDF 12mm
Build ground contours with suitable materials, any thing goes here as will not be seen in finished result. Corrugated cardboard works quite well with sections cut out like contour lines on a map. Unless your modelling a rocky area most ground lines follow a shallow incline and avoid drastic changes in contours.
Level of the `steps` between the ground contours with either papier mache or my favourite strips of paper laid on with watered down PVA glue and a brush (25-75 water-glue). With regards to the paper I`ve found that different grades of paper give different effects. Newsprint general use, Brown wrapping paper for extra strength and gives a nice smooth surface for water effects, Wood chip wallpaper starts the texturing effect.
Next get some sand -beech, building, silver, sharp all have different textures and effects in different scales, the main thing is that it needs to be bone dry, I often dry a batch in a hot oven/grill and store in jars for later use. Also you need a sieve of some kind, I use a cheap plastic teastrainer with a fine plastic mesh .
Paint an area with undiluted PVA, how big an area you paint comes with practice as the glue must be wet/tacky enough to glue the first layer sieved on using the teastrainer to give a level-ish covering. Add further layers to taste using different sized sands, scenic materials etc. Mix some PVA with water (50_50) adding a few drop of washing up liquid and using an eyedropper go over the whole base gluing down the sceanary ground work.
When dry I usually spray a ground colour on to suit but mix darker /lighter shades into this to give variation in ground colour. Dry brush onto this lighter shades of the original colour and when dry mix some raw umber or yellow ocher oil with white spirit and give an overall wash. *Note* if your ground colour is enamel paint coat the whole base with a coat of future polish to stop the white spirit lifting your earlier good works, when dry dry brush again and wash etc etc until satisfied with the result. Try dry brushing from a differentb direction on each layer for unsual effect. When you happy with the ground colour it time to start adding the vegitation. Here you can use scenic materials if you wish, but I tend to use a grass green in various shades and dry brush over the ground with a dark green wash in irregular patches.
IF I can get it to load here is a picture of my current work using this method.
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