how did the civil rights act of 1964 change the way voting was accomplished in many states?

Answer 1

Your question is based on a slightly misleading premise. First., the "Voting Rights Act" of 1965 ermpowered the U.S. Justice Department to monitor and sue various localities that had historically manifested racial discrimination if the US DoJ found that electoral practices within that locality discriminated on the basis of race or ethnic origin. As you might guess, these provisions were applied mostly (but not 100% exclusively) in electoral jurisidictions within the Old South\Confederacy. Remedies might include court injunctions against various polling station oractices, such as poll taxes or literacy tests which had historically been used to prevent African Americans from exercising the franchise.