you need to first ensure that your videos are unpredictable,for example whenever i see your posts on threespeak i can easily predict that on the video you will basically be facing the camera and start talking about the topic you want to talk about,but sometimes i feel you can try to surprise viewers by giving them something different,like you can sometimes create a video with less talking and showing them some lovely places in your country or some amazing things you find,you can show them some awesome tourist area in your country or show them some amazing houses...etc...just be different sometimes and be unpredictable,doing some contests too won't be a bad idea as a way to grow your popularity.....