Question

How exactly should you (what does it mean to) use appropriate eye contact, adequate volume, and clear pronunciation?

Answer 1

To keep eye contact and not to look away like your ignoring them

Answer 2

Eye Contact:

Look at them, and not like you're ignoring them.

Adequate Volume:

Satisfying volume, as in you hear them, and not some other talking, and making sure that you only hear them.

Clear Pronunciation:

Talking clearly, and not all slurred.

Example:

"I luh-ikee you too"