The fact that you are not getting outside your house it does not mean that you do not have to get dressed properly for an interview. The requiter asked you to have a Skype interview because he/she wants to see you. So make sure that you look presentable.
Do not forget that a Skype interview is supposed to be the same as a face-to-face interview. So all interview rules about body language, eye contact (try to look at the camera as much as possible, increase the distance between you and the camera if needed) apply here, too.
Make sure that your internet connection is working properly, including your hardware.
Make a test call a day before the interview at about the time of the interview. That will indicate you how the background looks, whether the lighting is enough and if there is any noise you sound take care of (if you leave with other people in the same house, notify them at about the time of the interview to be quite). It looks really bad when there are technical problems which you cannot solve fast and efficiently... especially when you are interviewed for an engineering job!
Tips: include your Skype address at your CV. If you do not want to give your personal Skype address, then make a new one with a neat naming and picture.
