We like getting something extra,especially at no cost.Therefore when you regularly ask yourself how can you serve your customer better,you might find new ways of making your loyal customers happier.

So called going the extra mile is also effective when it contains doing a favor first.Because by the rule of reciprocity we feel obliged to repay such a fovor.

Waiting for others to do something for you first doesn't work,think about making the first step,offer something extra and as for the benefits for you?They will come in bulk.