Cutting and trimming edges
Once the bulk area has been laid, you will need to cut pieces of hardboard to fit the edges. For rectangular pieces, simply measure the width between the last board and the skirting, and mark up a piece accordingly.
Cut the boards with a sharp general purpose knife, using a straight metal edge as a guide.
Alternatively, if you have a jig saw, you will find that this will make very light work of cutting boards.
Cutting hardboard round frames
The easiest way to cut awkward shapes is to make a paper template first. Use old newspaper or a piece of lining paper. Lay its square edge against the last board and, using scissors, cut the other edge so that the paper can be contoured to the awkward shape. Fold the strips back so that the paper fits the shape perfectly, and trim to this shape. Now lay the paper over the piece of hardboard and mark and cut this shape.
Lay exterior grade plywood panels in the same way as hardboard but leave an expansion gap of at least 10mm all the way around the edge of the room.