Here’s a great chord for playing Blues. It’s often overlooked as one of the important basic chords, but you just can’t play Blues without it.
Being a four fingered chord, it can be a little tricky to master first off. Start by building it by numbers - fingers 1, 2, 3 and then four. Strum from the fifth string down.
When playing blues in E with E, A and B7 chords, look for the short cuts when changing. E to B7 - your number two finger is common in both. Pivot from one chord to another. A to B7 - the first finger can simply slide into position along the fourth string.
Try it with a simple 12 Bar Blues, strumming Down, Down, Down Up, Down Up, (D D DuDu, 1 2 3+4+)
E E E E
A A E E
B7 A E B7