Here is the step by step .
1. Place the stir stix down ,length is up to you.
2.Cut foam core into thin strips around a 1/3 to 1/4 inch strips
layer them to desired height.let dry .
3. put Elmers glue on the sides,sprinkle CAt liter on.Let dry.Then put Watered down glues on it for a second coat let dry.
4. Repeat steps for 3 or 4 layers.on the second layer always add water down glue then let it dry.Then add regular glue then litter.
5.base coat black
6.Dry brush Grey,paint base
7.Add flocking and shrubs to the tops and sides.
8.put watered down glue on the top to help hold in place.
9.Seal it.i use cheap HAir spray for me.If you have spray tac glue use that.plus the sealent.
10.good to go.