1) Use a mix of ethanol (plain alcohol) and water. You can even burn your hand without doing harm to your self. It is important to experiment with this to find the correct ratio of ethanol and water. Too much water in it, and it won't ignite anymore. Too little water in it, and it really burns your skin.
This also is used in tricks for burning bank notesm without damaging them.
Use a little salt to make the flames look orange, otherwise you barely see the flames.
2) Take a concentrated solution of KNO3 and use paper, which is somewhat absorbing (no kleenex, that is too much absorbing). Write with a little brush. Allow the paper to dry (takes quite some time, so you should plan this in your show, using a hairdryer makes the drying much faster). You then can light the place, where text is written and a glow goes through the paper, at the place where the KNO3 was written.