- Once the polystyrene shapes have been glued to the hardboard (and sufficiently dried), use the knife to cut out the slopes on the hills. Start from the bottom, near the hardboard (leave an inch between the board and the cut) then cut all the way to the top, creating a slope.
- If you're making a stepped hill, this is when you glue the two parts of polystyrene to each other.
- Use the sandpaper to flatten out any uneven surfaces on both the polystyrene cuts and the hardboard. Here you can shape the slopes the way you want them, either as hard climbs or very sloping hills.*
This is how my hills looked after the second stage:
* If you want, you can cut out rocks and stony surfaces on the hills instead of flat slopes, and paint them up accordingly later. Since I'm going for a grass and dirt look for my terrain, I won't do much stones on these hills.