Setting and using options

setting-options.js

$.fn.footnote = function (options) {
        
    // This is the easiest way to have default options.
    var settings = $.extend({
        // These are the defaults.
        color: "blue",
        referencesLocation: "#references"
    }, options);
    
    // use the options 
    $(settings.referencesLocation).css("color", settings.color);
    
    //
    return //..
}

settings-caller.js

$("#myParagraph").footnote({
    color: "orange",
    referencesLocation: "#theReferences"
});