Here are a few examples of major chord voicings. Make sure you can see all the intervals between the chord notes and the root.
|Major 7||Major 9||Major 13|
Be careful to avoid open strings and non-chord notes ringing. As a general rule you should prevent the ringing from non-chord notes by damping them with a finger fretting a lower string.Strictly speaking a 13th chord should include both the 6th and the 7th. Two of the three 13th chords above do not contain the 7th so they would be more accurately notated as major 6th chords but for simplicity I have put them all in the same group.