Browsers have bookmark features to do it. Or people can save links of their most visited sites in their own ways (beyond bookmarks) for later use. No one can remember all site addresses.
You're right, however, for some cases (namely electrum) I still advise remembering it (electrum.org), just because one may need it on a fresh PC or a live OS.
But yes, for normal use bookmarking the proper site is also a great approach.
Anything, just don't search for it, because fake sites are often returned in the top of search results, and don't click onto links in e-mails, websites and so on.