If you're going to sell to an audience, whether it's a close friend or by placing an ad on a website, the key to making a sale is to know that audience. For example, if I have friends who enjoy cooking, or if I'm advertising with someone who has a cooking blog, I might direct those people to one of the people selling food or drink, promote products like PURJAVA to them, and so on. Target interests you know these people have, and you will succeed.