This can be the most successful way to earn money, and by money I mean hundreds and thousands of dollars monthly, depending on whether it is your only job or side job.
I will not detail too much in this post, I will just throw some important notes, and I will get down with details later.
There are 2 ways of making money from your youtube videos:
1 - become youtube partner:
all you have to do is make AdSense account, "monetize" your youtube account and connect these 2 accounts. Your videos will get ads, and you will get 1-20 cents for each click on ad in your video, depending on which country the click came from. So - your only job is to get subscriber army and tons of views, and I will get to it later.
2 - become partner with some of the networks on youtube:
in this case, you have to meet the requirements for network, such as 1000 views daily, 1000 subscribers minimum, no copyright strikes, and if you meet the requirements, you sign the contract, get support from network, banners, channel buttons and customized channel look and more. In this case you earn 1-6$ for every 1000 views. There are various networks such as Socialblade, TGN, Fullscreen, MAchinima etc.
In both cases, you have to follow the guidelines in order to avoid copyright strikes and account being banned:
For a video to be eligible, you must own worldwide distribution rights to everything in the video and the video must abide by our Terms of Service and Community Guidelines.
This means you have created everything in your video yourself, and you did not sell exclusive commercial usage rights to someone else. If your video contains content created by someone else, you must have their written permission to use and make money from it.
Examples of videos that could be eligible include:
You filmed your cat and there is no background music.
Your video contains royalty-free music, and you can prove commercial rights using direct links to the song and applicable license.
Your friend's band wrote and recorded a song for your video and states in writing that you can use and make money from it.
Which videos are NOT eligible?
Your video is not eligible if it contains content that you didn't create or get permission from its creator to use. You need to be able to show written permission for the following video elements:
Audio: recorded music, live performances, cover songs, background music, etc.
Visuals: images, logos, software, video game footage, etc.
Any other content you don't own worldwide commercial usage rights to.
Examples of videos that are NOT eligible
Your video contains a song you purchased for personal use (e.g., bought on iTunes or in a store) but didn't obtain a commercial license.
You found a video on the Internet and you cannot prove that it's in public domain.
You are only singing words of your favorite copyrighted song
You have used content from someone else without permission, but you haven't yet received a copyright notice on your video.
You edit together or "mash-up" other works
You only use 30 seconds of a song or video clip
Your video does not provide proper attribution or credits as required by a license.
If your video is not eligible, it may be removed from YouTube.
As I said, I will give you more detailed instructions on how to avoid being banned for copyright strikes and how to increase views.
Cheers!!