There are two ways to target an experience at users who click on links in your emails:
1. Use a UTM parameter within email links. For instance, you might add ?utm_source=newsletter to the end of all URLs included within your email newsletter (ex: www.example.com/article-name/?utm_source=newsletter). You would then enter /*?utm_source=newsletter in the include URLs field of the Pages card. That would include all incoming links ending with the ?utm_source=newsletter formulation. Alternatively, if you wanted to exclude newsletter readers from an experience, you'd put /*?utm_source=newsletter in the exclude fields of the Pages card.
2. Use a campaign code within email links. For instance, you might add ?tpcc=newsletter to the end of all URLs within your newsletter (ex: www.example.com/article-name/?tpcc=newsletter). You would then enter "newsletter" in the "campaigns viewed" field of the user segmentation card to include those readers in your experience.