You don't say how much musical knowledge you have away from piano. I play guitar, I've never studied piano and I don't own a keyboard instrument. But I can play bluesy stuff on the piano no problem. Here's a bluffer's guide to playing blues in the key of Am/C which is of course the easiest key to play on piano.
Right hand: Blues scale
A C D Eb E G. the Eb gives it the bluesy feel, especially if you play
A C D Eb!. You might get away with throwing in a B, but an F will sound way too jolly.
Left hand: play an
A5 (E+A, with the E low.) Following the blues progression, introduce
D5 (A+D) and
E5 (B+E). To give more variation, build up rhythms by adding 6ths and 7ths (the notes in between the ones you are already playing.
The opening of Beethoven's Fur Elise follows a blues scale an makes an awesome crossover piece if you change the rhythm slightly.
A5 I mean A with no third. This term is common in rock, not sure if it is used in classical.