The nice thing about polystyrene is the fact that you can cut, sand and scalp as you like.
The sanding seems to give it a bit more texture, shape and natural look.
Play around with the grit of sand paper, very fine sandpaper for the details and very rough (like you green sandpaper) to take chunks out of the polystyrene.
Using tile grout hides all the gaps and layers on the design.
You will see I used pieces of polystyrene to build the design, once I was happy with the look then I started to cut and sand, mostly sand.
Bearing in mind sanding is very messy, so do it in a place where you can make a mess and easy to clean.
Once I paint 5 layers of tile grout and a couple coats of paint you won't see any of the lines or gaps on the design.
Looking forward to seeing your project completed.
These are the pictures of the over all design, of the ones I posted above.
design (3).JPG
design (4).JPG
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