<div class="calendar">
   <table>
      <tr>
        <th><h4>PON</h4></th>
        <th><h4>WTO</h4></th>
        <th><h4>SRO</h4></th>
        <th><h4>CZW</h4></th>
        <th><h4>PIĄ</h4></th>
        <th><h4>SOB</h4></th>
        <th><h4>NIE</h4></th>
       </tr>
    </table>
 </div>

var Calendar = {

customDate: function (date) {
    return new Date(date)
},

currentDay: function () {
    return new Date().getDay();
},

currentMonth: function () {
    return new Date().getMonth() + 1;
},

currentYear: function () {
    return new Date().getFullYear();
},

getMonthDays: function (year, month) {
    return new Date(year, month, 0).getDate();
},

currentMonthDays: function () {
    return this.getMonthDays(this.currentYear(), this.currentMonth());
}

Calendar.createCustomCalendar = function (month, year) {

var currentDays = Calendar.getMonthDays(year, month),
    day = 1,
    monthDay = Calendar.currentDay(month, year),
    calendar = jQuery('.calendar'),
    table = calendar.find('table');

calendar.prepend('<h2>' + month + ' ' + year + '</h2>');


for (var row = 1; row <= Math.ceil(currentDays / 7); row++) {

    var tableRow = jQuery('<tr class="calendarRow"></tr>');

    for (col = 1; col <= 7 && day <= currentDays; col++, day++) {
        jQuery(tableRow).append('<td>' + day + '</td>');
    }

    table.append(tableRow);
}