hi we use lead for outlining the glasspaintings and like it is basically used for outlining
4 tablespoon white glue (it should be really thick)
1 teaspoon plaster of paris (powder)
1 tablespoon oil paints black colour (the one's which r in tin, not the tube one)
Next just pass the glue through malmal ka cloth so that its fine n clear. After that sieve the plaster of paris powder also. Then mix all the ingredients thoroughly n then put this paste in a cone (made out of plastic sheet).
Then its ready to use.
Note: When u will make the paste it will be in grey clour but when it will dry then it will turn black. You can use any colour in this lead.