Effective communication is about focusing on students and keeping an open mind. You can't be closed minded and you can't work on other things while the students are coming up to you.
We need to be respectful and engaging when interacting with students. If you have to talk to them about something negatively, like an advisement, we have to come back and help them through it and tell them how can I help you? If you don't then the student is going to think they have to do it on their own or the student will not put the time and effort in.
We have to help them and turn their weaknesses into strengths basically, just like that interview question, "What are you weakness."
We always need to keep an engaging attitude and be respectful when talking to them.