Watch the Step 2: Identify the Melody Note online guitar lesson by Frank Vignola from 1-2-3 Jazz Chord Melody
In step 2, we're going to match up the melody notes with chords from our chord vocabulary. For example, the first melody note in Take Me Out to the Ballgame is a C, so you'll go to your Cmaj section of your chord vocabulary and find the chord that has a C note on top. So as you just saw, we identified the first melody note of Take Me Out to the Ballgame, which is a C, we went to our moveable chord vocabulary and we came up with this C chord. This is the first chord melody to "Take Me Out to the Ballgame".