You can also look for characters that are easily identifiable. For example, assuming the text is in english, there aren't many options for a word that uses only

You can also look for characters that are easily identifiable. For example, assuming the text is in english, there aren't many options for a word that uses only a single letter. So the single character in the fifth line is most likely an "I" or an "a". These can also go into your chart.