Creativity is often, it not almost always a crucial aspect of critical thinking.  

With the explosion of the internet, social media, and access to more information than every before, we find people are still decidedly uncritical in their thinking (ie: buy into one positions or another on many issues and topics based on their tribe), or are incredibly critical in their thinking and question more and more of what they see. 

Flipping the classroom has the potential to eliminate the homework black hole for students who have difficulty understanding and completing assignments outside of the classroom.  

Closed questions are what most instructors use most of the time.  But increasing the use of open questions can help energize learning.  Furthermore, it is important to pause more often and for longer than you naturally think necessary when asking questions & calling on students, and even longer during follow up questions so students are able to think longer. 

Taking the time to observe how students are making use of the classroom/lab space early on can be very valuable. 

Managing classroom learning from the students perspective and incorporating various techniques to cater to a variety of learning learning styles. 

Float.  Very you location in the room.  Pause a few seconds when asking a question.  Make eye contact, for 3 seconds or so.  Vary your pitch. 

Variety is the spice of life, and essential when teaching students in the classroom. 

Introduce yourself and let the students introduce themselves.  Give an overview of what they'll learn. 

Keep a notepad to keep track of emerging requirements, questions, clarifying actions to take later, and supply challenges.