If you have an ecommerce site I would suggest indulging in social media marketing to get the " word out" about your site. Consumers seeking the opportunity to purchase from you have no idea your out there unless you make it a point to make your presence prevalent.
But allow me to answer your question before I go a little deeper into suggestions on ways to establish Customer Loyalty.
Customer Loyalty - Is a business/ service provider's ability to reward repeat customers with incentives, discounts, or cash back offers in return for the continued business provided.
Ways to build it :
1. Consumers - First you have to find customers. Ramp up your advertising and create a " buzz" around your company. Its key to create a level of intrigue by developing a campaign that outlines why your business is better than your competitor.
2. Points - You can offer points per purchase or credits. Customers can then cash out the points for a cash discount or for selected items.
3. Personal touch - Send your customers a birthday card, pay someone to pay attention to forums, reach out to your customer and establish a relationship with your customer that will influence a word of mouth review depicting your company as one of compassion.
4. Discounts - Offer customer's whom shop regularly a discount ( not everyday but special days of the month). This will influence these customers to refer others.
5. Affiliate Program- Offer points or a discount percentage off certain purchases based on the number of referred new customers. This seems to be a very popular option for online businesses.
6. Sneak Peak Days - If you have a new product being posted on your e-commerce site that you feel may interest a particular customer, send a description of the item and allow them to purchase it before it's made public. This creates a level of exclusivity.
I hope that helps