Communicating with your students is the core of an online class. Active and timely communication supports teaching presence and when instructors participate supportively and frequently students perceive the instructor as both enthusiastic and as an expert in the field. It's also more than student satisfaction on course evaluations.
Starting out as you mean to go along by communicating in a welcoming and supportive manner from the beginning with a personal and course introduction, an approachable syllabus, and an interactive introduction discussion sets the tone for the class. However, once you get into the term, faculty can have questions about response time and whether to use individual or group communication. Generally speaking, response to emails and other student questions should occur within 24 hours. Some faculty prefer to disconnect over the weekend, however, that is the time when most students are working and questions may arise. In that situation, you may want to indicate that you will respond to urgent questions only over the weekend. If you are getting the same questions repeatedly, instead of sending an email response to each student it is often more efficient to post an announcement to the entire class addressing the question. If what you are communicating would be helpful to more than a handful of students it is more efficient to share it to the entire group through an announcement or a Q&A discussion.
Re-assess when needed
If you find that, despite your best efforts, you are having trouble keeping up with grading and interaction, it's all right to stop and re-assess what you are doing and what you are asking your students to do. A mid-term check-in with your students via an anonymous survey is a good way to find out if they are also feeling overwhelmed, lacking connection, not understanding what is expected of them, or needing a different kind of feedback.
Communication