1. Firstly, you have to write what it is.
2. Secondly, write the main material it is made of.
3. Finally, write the properties that you can observe or measure.
(What is it?)This is a picture.
(Main material)It's made of wood.
(Properties)It isn't transparent, it's opaque. It's flat and rough. It's hard and stiff. It's not magnetic and it's insulator.
It's a square, it's 20 cm long and 20 cm wide. It weighs 22 g and it's colourful!