The D Guitar Chord (known as a D Major Chord) is most probably one of the first chords that beginner guitarists should learn. It is used in hundreds of Pop & Rock songs and is very easy to play.
The chord chart for a D Major Chord looks like this -
Start by putting your first (index finger) on the 2nd fret of the 3rd string. Put your 3rd finger on the 3rd fret of the 2nd string. Then put your 2nd finger on the 2nd fret of the first string.
Make sure that you only play strings 1,2,3 & 4. If you play strings 5 & 6 you will get a messy sound as strings 5 & 6 play the notes A & E which are not part of the D chord!