As HOH, it is essential to let your  TIH now that you love them and how much you love them.  Your TIH needs to know that they are loved and cherished; it will make them feel safe, secure & happy in your relationship.
The more loved and valued they feel, the more they will seek to please you by doing their very best at sticking to the rules.  Your TIH will hate seeing the disappointment on your face after they have broken a rule.

Remember a hug & I love you goes a long way.