With AdWords, you have the option to target broad as well as highly specific audiences via your remarketing campaigns. For example, you can target all visitors or only those who browsed certain product pages but did not convert. Segmenting who you remarket to allows you to tailor your ads to visitors you already know are interested in your website. You can further customize messaging with personalized ads based on what content someone browsed on your website.
If you have not done so already, go through the prompts to enable remarketing in your account and generate the Main list remarketing code. Add this code to all pages of your website.
Next, define your audiences or what segments of visitors you'd like your ads to reach. Here are some recommended audiences: