It comes as little surprise that most trusted brands are well-known names (see the Reader's Digest 2014 list, (www.rdtrustedbrands.com). But those awards come through years of consistent, trust-building branding and marketing. The good news is that those success stories can be applied to any product, brand or business.
Trust is built through experience with a brand, through advertising across local or global scales, and when consumers see how the brand reacts through traditional and social media to the challenges that can meet any product. The key tenet of trust is that the product works, and is seen to be working.
However, shoddy marketing tactics will damage the brand long before anyone tries it out. For new brands, maintaining an even keel is essential; don't make outlandish or cheap claims, give the brand an attractive personality, and don't create "shouty" or garish marketing campaigns (unless it is a particularly brash product) that will make potential buyers feel uncomfortable buying it. As the brand grows, develop messaging that reinforces the brand's strong points.
Once a brand is established, then marketers can experiment with slightly more avant garde approaches in different niche areas to expand the brand's awareness. As the brand grows, messaging through social media is essential, as this is where the family of brand users and potential ambassadors will congregate. Ensure your social media team maintains the same tone in their engagement as the branding, so as not to create confusing messaging that will alienate the fans, and to increase the level of trust they have in it.
Finally, when there is an issue with some aspect of the brand, ensure that a united front is taken across all marketing, social media and PR. First, quickly analyse the issue, talk to those affected and rectify the situation. Then, protect the brand in terms that consumers will understand. A quick explanation, an apology if needed and a promise to rectify or improve a process is infinitely more welcome than silence, denial, talking about it in dense technical terms and other approaches that consumers will see as "shifty" and will damage that hard-won trust.