I prefer to keep conversations together. Therefore, I usually will reply under your message. I may also move your message with my reply to a more appropriate place. (Usually that would be your talk page, if the discussion started there.) If I left a message on your talk page, I will watch it until you're back, or up to a week. So, in most cases, there's no need to notify me of your reply.
Hello, thank you for your recent contributions to an article relating to graffiti or graffiti culture! You may be interested in WikiProject Graffiti, a group working to improve Wikipedia's coverage of topics relating to graffiti. We would greatly value you joining our WikiProject, or adding some input at our talk page.