With a tuner.
Or play the b string and tune down the d string to match. Then play the low e string and tune down to match. Play the seventh fret on the low e string (now b) and tune the a string down to match that. Play the 2nd fret on the A string (now f#) and tune the b string to match that. Finally play the 5th fret of the D string (now b) and adjust the g string to get to that pitch.

Atleast that's how i do it without a tuner, there's probably a better way.
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Quote by lethaldosage45
buy a 7 string.

2 very different things

If you have a Chromatic tuner, you can do it easily, if you have a non-chromatic tuner, then tune the low E down to a B still on your tuner, and then tune the other strings to their relevant pitches off of that
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What is the easiest way to tune to Drop B?
Tune your low E string down so it matches your A string at the second fret.
then tune the a so it matches the E (Now B) string at the seventh (7th) fret.
Now, tune the rest of the strings by using the A string at the 5th fret to tune the D string, and the G string to the D string, then the 4th fret of the G string tune the B string down. Now use the 5th fret of the B string to match the high E string.
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Quote by lethaldosage45
buy a 7 string.

Absolutely not...

Quote by mashedpotatoes
Probably with a chromatic tuner

This, and your gonna have to restretch the strings for that low tuning, Also some really thick strings would help alot. What gauges are you using now?
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