Sidemenu

HTML

<div id="menu-button"></div>
<nav id="nav">
    <ul>
        <li>Главная</li> 
        <li>Контакты</li>  
        <li>О нас</li>       
    </ul>
</nav>

CSS

#menu-button {
    background: url('http://icons.iconarchive.com/icons/iron-devil/ids-3d-icons-20/32/Hamburger-icon.png');
    width: 32px;
    height: 32px;
    cursor: pointer;
}

#nav {
    position: absolute;
    background: #DDD;
    padding: 10px;
    left: -100%;
}
#nav.visible {
    left: 0;
}
#nav ul {
    margin: 0;
    padding: 0;
    list-style: none;
}
#nav li {
    margin: 0;
    padding: 0;
}

JavaScript

$('#menu-button').click(function() {
    $('#nav').toggleClass('visible');
});