Now you need to visit YouTube and log in. Then you can begin to find videos you like and copy their URL links.
-For IE users
Double-click the video thumbnail to open it and then copy the link displayed in navigation bar of the browser.
-For Firefox users
Simply right-click on thumbnail of the video and then choose Copy Link Location.
On YouTube, you can only copy the link of those videos with + left bottom corner directly. Those videos without plus mark need to be open by double-clicking and then copy the URL beside the video not the URL link displayed in navigation bar of your browser.