Just in case you are not familiar with tablatures, these six 
lines represent the following strings on the guitar
|=high e
|=B
|=G
|=D
|=A
|=low E

Here is how to play a "Db Major" chord.  There are 3 ways to play it.
A "Db" Chord is always composed of 3 different notes as long as 
its major.  Db, F, and Ab.  (b=flat)   

1: The basic Db Major Chord
|-1-|-->This is an F note.
|-2-|-->This is a Db note.
|-1-|-->This is the Ab note.
|-3-|-->Here is another F note.
|-x-|-->Dont play this string
|-x-|-->Dont play this string

2: The E-string "Db Major" Power Chord.  This is one of the many 
power chords commonly used in rock music.  All E-string major 
power chords use this same fingering, so it is important to remember 
this fingering.  It is also easy to play any power chord because 
you will get used to holding your fingers like this.
|-9--|-->This is a high Db note.
|-9--|-->This is an Ab note.
|-10-|-->This is an F note.
|-11-|-->This is a Db note.
|-11-|-->This is an Ab note.
|-9--|-->Here is the Db note.

3: The A-string "Db Major" Power Chord.  Any A-string major power 
chord has this fingering as well.  That is why power chords are 
so easy to play.
|-4-|-->This is the high Ab note.
|-6-|-->This is an F.
|-6-|-->Here is a Db note.
|-6-|-->Here is an Ab note.
|-4-|-->And a Db in the bass.
|-x-|-->Dont play this string.

These are the fundamental "Db Major" chords in the guitar world. 
 You actually can take any combination of the notes Db, F, and 
Ab and make a "Db Major" chord out of them.  But to tell you the truth, 
you will never find yourself using any other combination than 
the ones shown here.  So good luck, and practice the fingering 
of these chords.  After that they come naturally to you.