Well, it's very easy! I've been asked so many times about this matter that I've lost the count. Anyway I though why not write an article about it and give the link to them.
OK, let's start with the Video.
Open the site called www.clipconverter.cc and then go to YouTube and open which ever video you want get a portion from.
Copy the URL of that video (which you will find at the top) and paste the URL in the box on www.clipconverter.cc
Choose the video format you like MP4, 3GP, AVI or MOV then choose where you would like the video to start from and where you like the video to end, and then click "continue".
Choose the video Quality and click on "Start" or you can click on "Download" aswell, but in that case it will not convert the original YouTube video.
It's done now you can download the video.
Note: If you want to download audio then use the same method but choose audio format like MP3, M4A or AAC
That's all for this post. Enjoy!!!