how to change crossover and mutation in GA to get better performance?

i have my own ga code and want to improve performance of ga so how can i do changes in crossover or mutation

[Walter Roberson]

Duplicates http://uk.mathworks.com/matlabcentral/answers/263983-how-to-change-mutation-crossover-selection-population-size-or-some-parameters-in-ga-and-bpso-to-impr