Brand affinity is the technical term for why you wouldn’t be caught dead drinking Coke if you’re a Pepsi fan. Or driving a Chevy when you have always bought Fords. Or buying an Android phone over an iPhone.

We tell ourselves it’s the taste. Or the performance. Or any number of logical-sounding reasons designed to make us feel like we’ve based our purchasing decisions on something very reasonable. But if we’re honest with ourselves, we have to admit that it’s our feelings about a brand that often make us choose one over another.

Brand affinity can be an important part of why your customers regularly choose you. But how do you build brand affinity without the budget of big brands like Apple, Ford, and Coke?