Here is a nice tool I came up with, rather then trying to flip each breaker and see if you found the right one, this little doohickey will automatically isolate the circuit you are working on AND flip the breaker for you
Safety glasses and proper gloves reccomended.
I have a pair of side cutters that work for that too,now they have a built in wire stripper. Buddy insisted the breaker could stay on,as the switch was off. The electchicken wired it bass-ackwards....