Building a memory/matching game. I want to start with 6 divs, clone them, and randomize the order. At this point I have an array with 12 items. Is this correct so far? I've found some functions to randomize the order of an array. That shouldn't be a problem. Once I have that, is it fastest to do a for loop and .append() to the page? Or should I …

gistfile1.js

this.$initialCardCollection.length = $('.js-memory-card');
this.fullCardCollection = [];

// this.$initialCardCollection.length has the original divs on the page that i'll clone.
for ( var i = 0; i < this.$initialCardCollection.length; i++ ) {
  var $thisCard = $(this.$initialCardCollection[i]);
 
  this.fullCardCollection.push( $thisCard );
  this.fullCardCollection.push( $thisCard.clone() );
 }
 
 

    // Build array with duplicates
    for ( var i = 0; i < this.$initialCardCollection.length; i++ ) {
      for ( var index = 0; index < 2; index++ ) {
        this.fullCardCollection.push( $(this.$initialCardCollection[i]).html() );
      }
    }

I put a for loop in your for loop so you can loop while you loop