Your speaking voice and how you sound is so important when interviewing via Skype!
Skype interviews are used as a last resort when looking at candidates for a job because it's a dreadful way to communicate, compared to a 'face to face' interview. They are often used as a preliminary way of screening candidates when schools in Thailand hire from abroad. They are also used by schools outside Thailand to 'poach' teachers. Myanmar does this a lot!
Sure, you can get the lighting and sound adjusted for optimum performance and you can even tweak your internet connection so it won't be interrupted... but if your prospective employer can't understand you then that job may slip through your digital fingers!
It's hard enough for Thais to understand English, and without the body language and other advantages of a 'proper' interview, you may find yourself either having your statements misunderstood or simply not being understood at all.
Here are some basic ideas that may help you to cruise through an online interview and overcome the handicaps that this type of interview poses. These ideas should also help you even if the interviewers are themselves native speakers.
As this list is a long one and the subject matter is unending I'll just highlight some points of importance and you can follow up these by Googling for more information.
1 - Breathing! Take deep breaths and calm yourself before the interview starts.
2 - Before the interview, practice enunciating your answers. Read answers to questions into your phone or computer and play them back. How do they sound to you? Cut down on the 'umm's and 'er's!
3 - Slow down the tempo and turn up the volume of your answers and say the words clearly. You don't have to sound condescending to pull this off and you may want to practice this before the interview.
4 - Think about your answers before you say them out loud. The interviewer won't mind waiting a few seconds, especially if the pay off is worth it to him or her.
5 - Learn to listen! One hurdle of this (or any) type of interview is that you are giving answers to questions that nobody has asked. Listen to and understand the question and return a pithy and considered response.
6 - Open your mouth when you speak! This is unbelievably crucial and will go a long way to helping you to be better understood.
7 - Inflection, inflection, inflection! Monotonous speech is boring and difficult to understand, especially on the phone or in a video interview.
8 - Finally, don't try to be funny. Your light-hearted banter won't translate well over the internet and you'll look unprofessional. Interviewers will be able to gauge your personality well enough, without you having to resort to jokes and off-topic anecdotes.
Like I say, this is a subject that can be explored forever and I've covered just some brief points. But if you just follow these, you'll find your online interviews will go a lot better than you had even hoped for.