For a modern, permanent decoration you can fit expanded polystyrene tiles
1 In most rooms the electric light pendant is central. Even if it is not, you should see that the ceiling rose is either at the edge, corner or exactly in the middle of a tile. To do this, draw a line from the centre of the rose to the centre of the nearest wall.
2 The first tile is applied right up against the ceiling rose with a small curved piece cut from the corner to fit about the rose itself.
3 Further tiles similarly cut are fitted round the rose. (The alternative is to so arrange the ceiling tiles that the rose fits through the circular hole cut ;n the middle of one of the tiles.)
4 First fit an entire row of tiles dead straight along the line marked to the wall.
5 Then working at right angles, lay another row to the adjacent walls. Finally fill in the spaces between.
6 Although it has been traditional to fasten tiles of this kind by using four or five blobs of cement, we recommend that you use a strong adhesive (such as a heavy-duty Polycell) evenly distributed over the whole of the tile back.
7 Where you have to cut tiles the best tool is certainly a razor tool like this Stanley razor knife, it makes a very clean cut indeed.
8 To make a matching bevel on the cut edge, shift your straight edge inwards by about half an inch. Then tilt the tool and draw it along taking away a sliver of the polystyrene.
9 These pieces can then be fitted right up into the corner and edges of the room and look quite effective with no further treatment…
10 as you can see
11 However, for a final improvement you can fit special quarter round coving which is simply glued into place.