I believe the word means being cautious in this context.
“Constance Culmington, he reflected to himself, was exactly the sort of woman who would buy an island and surround herself with mystery! Nodding his head in gentle approval of his logic, Mr. Justice Wargrave allowed his head to nod... He slept..." Chapter 1, pg. 3
Trust to me means you can be open to someone because you know they won’t go around telling what you told them. You aren’t hesitant to tell them something
Maintain skilled and graceful
