Here are 4 final tips for avoiding some of the more common mistakes:

1. Tie your major applications to the major points of the passage, not to tangential points, unless you have a really strong reason for doing so. Give more time to applications that come from the more major points

2. Always ask before making an application "can I see how this passage links to God's big purposes in creation and redemption? And most of all can I see how it leads people to his Christ as the highpoint of the story line of the Bible?" If you can't, or find you are forcing it fairly randomly (eg I can't see how the tassles on the garment of the high priest are about Jesus but they MUST be, so I will say they are - don't laugh, I have heard it done), then you probably are not yet making pointedly powerful applications from the passage

3. Don't do moral example application before doing salvation history application. Sooner or later it turns into mere "blessed thoughts" or moralism. The Bible becomes simply a set of lessons about how I should live my life rather than how I pursue Christ and live in God's salvation for God's purposes

4. Don;t assume that what God does for Bible characters he will do for me. That way we only choose to apply the bits where nice things happen. We will talk about God protecting the baby Moses and apply it to us but we won't talk about God allowing the slaughter in the innocents in the subsequent passage because we wouldn't want to apply that to us. Which tells us that our applicatory principle is wrong