Write the notes from Eb to Eb as it would appear on a piano. Eb-E-F-Gb-G-Ab-A-Bb-B-C-Db-D-Eb. Assign each note a number based off of its position from the left. So, Eb=1 E=2 F=3 and so on. There should be 13 notes.
Determine what key your original song is in. Lets say it's in the key of "C".
Write notes from C to C. So this would go, C-C#-D-D#-E-F-F#-G-G#-A-A#-B-C. Assign each of these notes a number. The notes should number 1 to 13.
Transpose the notes or chords in your original song using the chart you've created. This way a "6" in one scale will have the same chordal position in another scale, even if the key is different. If your original song goes 1-6-8, or C-F-G, then your song in Eb would go Eb-Ab-Bb.