The commonest problem that those regularly teaching and preaching have, is drought. Ideas dry up and you find yourself scratching around for a topic and material. Fortunately this is any easy problem to solve.
Not divine inspiration. But inspiration from your own subconscious mind. It is a computer that can, with the right programming, give you ideas and end the drought. Two things are necessary:
Tirelessly, while you read, talk, listen, observe, think, even dream, your computer scans and integrates the input so as to obey the command you have impressed conscious will reinforced with emotion and visualization. The ideas will come in flashes which, like dreams, are quickly forgotten unless recorded. The quality of these ideas depends on the quality of the input. If you think, talk, and listen to drivel, the ideas you get will be drivel.
Compile a comprehensive list of everything a preacher should preach on is a handy tool to suggest something to preach on next. It helps end the drought of ideas. First write down every topic YOU can think of, then consult subject indexes in appropriate books, for example: Hymn book, Naves Topical Bible, Bible handbook or dictionary, Concordance, Periodicals, etc.
Not a literal pot but a cardboard folder, in which several sermons are in various stages of completion. No junk! Keep the pot replenished, keep it stirred, keep it on the boil. It is a good idea to set aside a time each week to work on the contents of this folder. To use another metaphor, this folder is a reservior of ideas to use in time of drought. Don't let it get stagnant