I feel one of the most important thing you can do to build rapport with the students is to show them that you do not know it all and make mistakes. Being a technical Instructor I some times but out wrong information. When I do, I'll get the whole class together for a "Pow Wow". This gives me the opportinity to correct my mistake and shows them my human side as well. One other note from past experince. If you are sitting in another Instructor's class and he/she makes a mistake get with them on a break and talk about it. That way after break they can make the correction with the class themselves. Never try to correct he/she in front of the class. Doing so causes them to lose creditability.