To get more people to watch your videos the best chance you have is to have YouTube suggest your videos. So what you actually need to do is get YouTube to want to suggest your videos in order to grow your channel. So how can you get them to do this?
One thing that YouTube loves is videos that have a high retention rating. If you get people to watch your video for a longer period of time, the YouTube algorithm will suggest your video to more people. So in order to do this you need to keep your audience engaged.
Besides just making excellent videos that people will want to watch, you might not always have exciting action footage or beautiful white sand beaches for people to glance at. You might be making a talking head video where you share information. Still you need to keep the audience engaged and keep them from clicking away to the next video.
Your can start by hooking them and explaining or showing what to expect from the video and what the pay off is for them to watch until the end. That way they get invested in the video and once they want to see what you promised them and you can keep them engaged during the video they are less likely to click away.
A way to keep them engaged is by changing up the image on screen. Every 5 seconds you should have something different for the viewer to notice. This can be a different camera angle, a close up shot, some B-roll or even just a banner on screen or a call to action in the form of a subscribe button that pops up. Anything that draws the attention and gets the viewer to notice something new is something that keeps him from tuning out. By changing it up you speed up the pace of the video for your viewer. It will seem to go faster and they will watch your video longer. As a result YouTube will suggest your video to more people, who will also watch your video longer and YouTube will suggest your video even more.
So really all you need to do is hold the attention of the viewer and keep them engaged.