The first step in order to learn this chord is to relax your palm. This is because you will almost be holding a bar chord and if you are new you will most definitely find it difficult to hold down this chord for a long period of time. Simple put your palm under the neck and use your thumb to hold down the guitar firmly.
Once you are done, you must start off by leaving the bottom most E string free. This means that this string will be ringing free when you are playing this chord.
The second last string, also known as the B string, will also be left open. This string will also be ringing free when you will play the chord.
The third last string, also known as the G string, will be used. Your pinky finger will come into use as you will hold down the fourth fret of this string with your little finger. The fourth fret is the A# note on the G string.
Now you will use your ring finger to hold down the fourth fret of the D string, the string which is right above G which you played in the previous step. This is basically the F# note which you will be playing on this string.
The second string from the top, also known as A, will also be used. You need to hold down the second fret with your index finger. The note you are holding down is known as B.
In the end either you can mute the first string (E string) or you can play the second fret in order to add more feel to the sound.
So basically you will be playing a muted first string, B note, F# note and A# note while B and E strings are left ringing.