What do you need?
paper maché
the cardboard skeleton of the volcano
acrylic paint
paint brushes
moss (@ the Garden Center)
gravel & pebbles
twigs
hobby-glue
The glue thickness is good, the newspaper shreds in the bucket are mush. Knead both together quickly with your hands and start!
Model the paper mache all around the vulcano skeleton.
Bit by bit until the skeleton is fully covered.*
Mix for the base coat green paint with some yellow.
Cover it with ocher, a lot of yellow, a touch red and a drop blue.
* Put the volcano aside for a week so the paper mache can dry thoroughly. Now you see where the edges are nedded. The bottom warps because of the moist but it will recover when dried. If the weather is dry put the volcano outside in the sunshine, on a wire rack so it can dry underneath as well. You can not paint before the volcano has dried througout. Let the layers of paint dry overnight in between!
The next day mix grey, a lot of white with a drop of black and paint all over the volcano. Do not cover the first layer completely, leave tiny bit open so you can see green and yellow come through. Let the paint dry again!
In the mean time you can make trees, twigs with moss. Stick them into the volcano with some glue. When the volcano has dried cut off the edges all around and stick moss and gravel on, it will look even nicer!