On my side of the bed, the top sheet must never be tucked in. Never, ever!
At night, just like during the day, I need to move; otherwise, come morning, I’ll look like I have a bad case of rigor mortis!
Tightly tucked sheets confine my feet, forcing them into ballet-like positions that my feet have no business imitating.
For those who really must, here is how to make a bed – “rack” in Army lingo – with hospital corners:

