When you start a new series consider whether it’s time to be more overt with some study instruction. This is especially helpful when shifting to a new genre. For instance, after spending some time in an epistle you shift to a series from Proverbs. Help people re-orient themselves by deliberately setting aside a message to communicate the basics of Proverbs – how they work and how to study them. By demonstrating this with a particular proverb the sermon still has definite value in itself. However, if you are able to equip people to study the Proverbs for themselves, then the sermon’s value is inestimable.
Instructing and equipping people to handle the text should be an ongoing project, but why not let that project boil to the surface when moving into a new genre (Psalms, Proverbs, Parables, Prophets, ePistles, etc.)