One command that's burned into my muscle memory is
gv. This starts Visual mode with the previous area selected. I find this useful for shuffling around blocks of text or applying commands to selected regions. Some commands clear a region, so quickly typing
gv to get it back is great.
There are arguments to avoid Visual mode for certain classes of operations, but I find it useful for performing refactoring, or stylistic changes. Practice
gv if you're not used to it.
I often want to do the opposite as well: after putting (pasting) something I may want to visually select it. This isn't as easy as
gv, and it took me a while to figure it out --
`[v`]. It works like this:
`[: Move to the first character of the previously changed text
v: Enter Visual mode
`]: Move to the last character of the previous changed text
This is harder to learn, but user-friendliness is only a
nnoremap away. See Selecting your pasted text for more.