Well by "subscribe link" I meant making a link which you can put it on your website, Facebook, Twitter or even inside of your Youtube video as an annotation. When people click on that link, it will take them to the channel page and ask them to confirm like the picture below.
Let's see the URL. https://www.youtube.com/user/mozartips?sub_confirmation=1
OK, When you try to make URL for your own channel then just remove the mozartips from the URL above and type your channel name instead.
For example: https://www.youtube.com/user/BBCWorldwide?sub_confirmation=1
I hope this small tip will help you to grow your subscribers.