You can either accept Vertcoin via a payment processor that accepts cryptocurrency and gives you your local currency, or by integrating the Vertcoin wallet into your payment system. Vertcoin is almost a drop-in replacement for Bitcoin so if you already support Bitcoin, Vertcoin should be trivial to support.
Payment gateways accept Vertcoin on your behalf and give you your national currency in return. CoinPayments is currently the preferred method of accepting Vertcoin for your online business. CoinPayments charged an 0.5% fee for its services and has integrations with various popular e-commerce platforms including WooCommerce, Xcart, drupal and wordpress.