Hakema can be added in many ways. To add as a booking button next to each service, insert the following code
<a href="your free business page address" target="_blank"> <input type="button" style="background-color:#00d1c1; color:#fff; border:5px solid #00d1c1; height:40px; width:160px;" site="hakema.net" value="Book Now" id="widget-booknpay"> </a>
You can customise color and size of the button using background-color, heigh & width parameters.
You can see some examples here.