If you use the @FediFollows directory (at https://mastodon.online/@FediFollows/108521414258703203), when you click on an account's follow button it will ask you to enter your own Mastodon address, in a process called "remote follow".
Remote follows are annoying as you have to keep entering your details again and again, even though you've already logged in on your home server 🤬
Fortunately, there is now a solution, a new plug-in for Firefox browsers called "Mastodon Simplified Federation":
When the plug-in is installed, you don't need to enter your address any more when doing remote follows 👍
The plug-in is written by @rugk and you can find out more info at https://github.com/rugk/mastodon-simplified-federation
(Thanks @aral for mentioning this plugin!)
And for people using #Friendica:
Go to your settings, select the "Display" tab, and under "Content/Layout" section you can find an option called "Stay local". Enable that option and click "Save settings". Next time you click on someone's profile you won't be redirected to a different instance, it'll stay local so you can follow them directly 😉