Dextrin 10%
Black Powder 90%
Grease paper
Sharp knife or long ruler
Wooden board 1.5 feet by 1.5 feet (the board will have to be varnished on one side or have some other non-stick coating on it or the black powder paste will all get stuck to it)
Simply add the black powder and dextrin together in a plastic container. Now add enough boiling water to make the mixture into paste that will stick together when pressed between two fingers. Now spoon this mixture out onto a large sheet of grease paper. Now flatten this paste down with your shiny coated wooden board, try to flatten the paste down so the height of it is all even (i make them 1cm high). Take your long ruler or long knife and push the paste into a square shape, by simply pushing all of the sides of the paste so they make a square shape. Now take your ruler or long sharp knife and 'cut' the the paste, starting from one of the square adges, however high the stars are from the grease paper, cut them that size along everytime you cut the paste (say if the hight of the paste was 1 cm high, cut the paste 1 cm from the edge). Once you have cut the paste up into long rectangular shapes, start cutting accross them to make small square shaped stars, once again, cut them from one edge at the same length as before (1 cm). You should now have 1 cm squared blocks of paste. Leave these stars for 24 hours to dry in a warm room or in the sun if possible.
You could make these burn white and shoot white sparks out buy adding 10% fine aluminium powder. The composition would now be 80% black powder, 10 % aluminium powder and 10% dextrin.