1. Think yourself empty. Survey a passage of Scripture in the proper spirit of unlearnedness. Avoid the proud assumption that you initially know what everything means.
2. Read yourself full. Read widely and regularly.
3. Write yourself clear. Aside from the essential empowering of the Spirit, freedom of delivery in the pulpit depends on careful organization in the study.
4. Pray yourself hot. Without personal prayer and communion with God during the preparation stages, the pulpit will be cold.5. Be yourself, but don’t preach yourself. There is nothing quite so ridiculous as the affected tone and adopted posture of the preacher who wishes he were someone else. Also – a good teacher clears the way, declares the way, and then gets out of the way.
This comes from Beggs book Preaching for God’s Glory.