Many popular songs including "Big Yellow Taxi," "She Talks to Angels," "Even Flow" and Bob Dylan's entire "Blood on the Tracks" album have been played in open D. Below, you will see how to tune from standard tuning to open D.
Use the fourth string as a reference to tune your sixth string. Pluck both the fourth and sixth strings simultaneously while slowly tuning down your sixth string until it matches.
Now that you have tuned the sixth string to D, use this to tune your first string to D as well.
Lower the second string to an A using the fifth string for reference.
Lower the third string to F#. It is easiest to use the fourth fret on any of your D strings to do this.