Don't try to do it overnight. Practice always before you use something. Try only what is value added from using technology, that is, if a drawing, a transparency or a Textbook photo is better by all means use it instead. E veryone has some disasters.
Students tend to be tolerant.
Always have a Backup plan if the technology fails. Always allow extra time, especially on Exams using technology. N o, I have not had failures, yet. Don't forget to keystroke your instructions before you give them to the students. Hardware breaks regularly, preferably when you are trying to do a demo in front of 150 students.