In the following chart you will find another method to play Melodic Modes. For many guitarists, it's more comfortable to play three notes/string. Another advantage of this method is that it allows fast crossing from position to position.
The next table shows the correspondence between the root of the scale and the fret on the guitar where a certain scale should be played. For instance, if you want to play in the root of A, you should start at the 5th or 17th fret, for the root of C, you should start at the 8th or 20th fret, for the root of Eb, you should start at the 11th fret: