How to A/B Test Web Forms for More Conversion

I want to customize my website form to look it more attractive and responsive. Presently i am not using any form in my website: http://www.trinfortrinservice.dk/ .. a little bit confused. what web forms would be good fit for my business and how can they help me in conversions?

Well you can add a contact form. So that customers can contact you.

How to Set Up a Contact Form in JotForm

Or you can add a payment form. So that customers can select products or services and pay for them.

Setting Up Your First Order Form