1. Manage your time. Posting and responding to posts takes time. Sometimes it takes a few minutes, sometimes it can take hours depending on what is being asked of you or what you feel you need to post.
2. Timely Responses. Instructors can set time limits on opportunities to respond to posts so you need to check your assignment due dates and plan accordingly. Also, if you post a response and are asking for/expecting replies, check your posts frequently and reply in a timely fashion. Online this usually means within 24-48 hours.