Read this line from Hamlet discussed in Shakespeare: The World as Stage.

No one set scenes more brilliantly and economically than Shakespeare. Consider the opening lines of Hamlet:

Barnardo: Who's there?

Francisco: Nay, answer me. Stand, and unfold yourself.

Barnardo: Long live the King!

Francisco: Barnardo?

Barnardo: He.

In five terse lines Shakespeare establishes that it is nighttime and cold ("unfold yourself" means "draw back your cloak"), that the speakers are soldiers on guard, and that there is tension in the air. With just fifteen words—eleven of them monosyllables—he has the audience's full, rapt attention.

How can the Early Modern English expression "unfold yourself” be paraphrased to better understand its meaning?

put your arms up
turn around
remove your cape
explain yourself