I'm suprised no one has mentioned it yet, but List::Util has a shuffle() method that does just that.

use List::Util qw( shuffle ) ;

my @arr = qw( a b c d e f A B C D E F ) ;

print( ( map { "[$_]" } @arr ), "\n" ) ;
for ( 1..5 )
{
    print( ( map { "[$_]" } shuffle @arr ), "\n" ) ;
}
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Those who know that they are profound strive for clarity. Those who
would like to seem profound to the crowd strive for obscurity.
            --Friedrich Nietzsche