well, it's just a B chord with an A in the bass, so you could try:

e--x
b--4
g--4
d--4
a--0
e--x

or:


e--x
b--4
g--4
d--4
a--x
e--5

they're probably the easiest options. If the chord you're playing is part of a 'walking bass' section where you work up or down, the root on the fifth option gives you more freedom...

You can find all sorts of chords at looknohands.com