First of all you need to understand how to play a bar chord. It is necessary because a bar chord comes in handy whenever you are playing a B minor chord. This way you will be able to hold down the entire second fret of the six-stringed guitar and you will only have to adjust the other three fingers.
Simply use your index finger to make a bar from the second string to the last string. This means that all the five strings: A D G B and E will be barred on the second string with the help of your index finger.
Now you need to play other notes on three different strings as the first string will be muted because you want your chord to start with a B.
Your second string will be playing the B note automatically since your index finger is covering the entire guitar. This means that the B note is being played on the A string.
The third string, also known as the D string, will be playing the F# note. This means that you will have to put your ring finger on the fourth fret.
The pinky finger will be used to play the fourth fret of the next string. Musicale you will be playing the A# note on the G string.
The last thing you need to do is to use your middle finger. This middle finger will be used to play the third fret of the second last string. This, in musical theory, means that you will be playing the D note on the B string of your guitar.
The overall chord progression looks exactly like this: X 2 4 4 3 2.
However, some people use 2 2 4 4 3 2.