1. Select an appropriate coloured or plain mat board and cut it to the external measurements required. Do not cut the window.

2. Select appropriate watercolours or acrylics in the colours to suit the artwork.

3. Mix the paint with water until a wash consistancy is achieved.

4. Damp the sponge in water and wring out.

5. Put the sponge into the paint and then apply it to a test piece of mat to check the colour and texture produced.

6. If the effect is suitable then sponge the surface of the matboard.

Note: In between each impression of the sponge rotate your wrist so as to present a different surface of the sponge to the mat. This will avoid any repetitive patterns forming.

7. When you have achieved an even coverage, put the board aside to dry.

8. Repeat stages 3 - 6 for up to three colours or tones.

Note: Usually two or three colours are more than enough to give a satisfactory finish.

9. When the mat has dried thoroughly, cut the window to fit the artwork.