To add a new quote in slider copy/paste a slide item.
<div class="quotes component owl" data-config='{"items": 1}'> <!-- slide item --> <div class="quote pl60 pr60"> <p class="text fw3 fsi fz3 ac lh16 mb30 mt50 lighttext">Quote</p> <p class="text fw3 fz3 ac mb50">Quote author</p> </div> </div>
In data-config attribute set properties for your slider.
Check the full documentation for more info and properties.