I should warn these will not last indefinitely but are a fantastic gift and or addition to your table settings.
I used a bought cardboard/chipboard sort of thing square. Although you could just use thick corrugated card.
I covered the squares using either pva or glue gun glue to fold the paper over the edges as if you are wrapping a parcel.
Because it’s got to be flat I lined up an image already printed on the paper for the centre of the square.
I made the top slightly waterproof by placing acetate square over the top of it. Make sure you use glue that will dry clear so you can see through to the image below.
Your coasters will be ready to use once the glue dries.