Give some incentive to new customers?

Hi there,

I'm busy building my online store (using Mijoshop Opencart integration for Joomla) and I would like to add some incentive for new customers - like an automatic discount on your first purchase, or generating a 10% discount voucher for people registering for the first time etc.

Can you give me any advice on which would be the easiest way to give some incentive to new customers and point me in the direction of extensions necessary to achieve the functionality?

Ada