• Make sure you're both using Skype, as some people mistakenly believe they can use any programme, phone, or computer with a camera. Also, if the person you're speaking to's video feed is slow to appear or irregular, it could be due to a sluggish or choppy Internet connection on one end or the other.
• Furthermore, downloading large files without enough bandwidth to handle them can degrade video quality, even to the point of preventing the other person from showing up at all. A direct connection to an Internet modem or router, rather than a wireless connection, will provide you with superior video quality.
•  Make sure the option to 'Hide Myself' or 'Stop My Video' is not chosen when the individual right-clicks on her Skype screen. Also, if neither of you has the most recent version of Windows 7, XP, or Vista, or if neither of you has the most recent version of Skype, Skype may not be able to show video.
• Check to see if any other programme is trying to use the webcam. Video editing software, instant messengers, browsers, virus scanners, firewalls, Windows Explorer, and even some websites are examples of such software.

Read More: Why can't people see me when I call them on Skype?