In the beginning, for questionnaire, I will find existing instrument involved in my topic. Existing instrument is instrument which has been developed by previous researchers. This kind of instrument, it was ensured about validity and reliability. However, it is not easy to find existing instrument which is similar with my research, I have to develop questionnaire by creating appropriate questions for achieving objective of study. After that, I have to do pre-test instrument with small groups who have characteristic similar with target group of the study and test validity and reliability value as principle of statistic. This testing is importance to establish the content validity and reliability of an instrument and to improve appropriate questions and format of instrument.