A cold audience is one that is either completely unaware of your brand or is only vaguely familiar with it. They may have used a similar or related product in the past, but they don't really know what your company is about. Reaching cold audiences takes more time and effort than warm audiences, who already know about you and are interested, but it's necessary to make the effort, especially for new businesses.
You need to do thorough research on your targets before starting any advertising or email campaigns. While they may not know your brand or product, they should at least be the type of person who might be interested if they knew. Consider age, education level, income level, stage of life and any other relevant factors.
Recognise each demographic's problems and explain how your product or service solves these problems and makes life easier for them. Focus on the problem first to get their attention. They're more likely to read on if they see something they identify with.
For cold audiences, trust is low, so you need to offer a lot of value to build that trust. Any chance to get something for free is an attraction, so consider free samples and free trials to let customers try your product and learn about it for themselves.
Being informative about subjects related to your product also helps to gain trust. Entertaining articles or videos on how to do something using your product or on the history/background of your product or a related topic captures people's interest without making them feel that they're being subjected to a sales pitch.
Do research on your targets
Recognise their problems and present solutions
Offer value at no cost