What is a one-sentence summary of the following article?
If you're not already signed in with your Google account, click SIGN IN at the top-right corner of the screen to sign in now. It's not possible to open your subscriber list using the mobile version of the YouTube app. This opens the menu. It's near the top of the menu. It's one of the blue buttons near the top-right corner of your profile. It's at the top-left corner of the page above your channel image. This displays a list of users who've subscribed to your channel. Only subscribers who make their subscriptions public will be shown on this page. There's no way to display subscribers who hide their subscriptions. This takes you to that subscriber's channel. It's near the top-right side of the subscriber's page. It's under the "Stats" header in the far-right column. A menu will appear. This removes the user from your list of subscribers and prevents them from communicating with you. Blocked users will not be able to comment on your videos.

Summary:
Sign into https://www.youtube.com. Click your profile photo at the top-right corner. Click My Channel. Click CUSTOMIZE CHANNEL. Click (number of)subscribers. Click the name of the subscriber you want to remove. Click the About tab. Click the flag icon. Click Block user.