This is a challenge. An easy solution to the problem of boredom and sermons is to not preach ... tell jokes instead ... show a film. But that is no real solution!
A joke or two can help; and certainly telling an engaging story captures congregational attention. As someone once taught me, tell it in the middle and not at the beginning!!
But somewhere in the sermon we will want to give a bit of 'decent content' - some teaching, some doctrine, some theological meat on the bones of the structure. How to make this not boring?
Here are two thoughts:
(1) Language itself can engage attention so choose good words. A recent sermon, for instance, reminded me of the power of contrasting words. Compare these two descriptions:
"Jesus was tough and tender" and "Jesus was able to be assertive as well as to feel sympathy for people and the difficult situations they faced".
The first statement is short (so less likely to lose the attention of its hearers), engaging (the use of contrasting words tough/tender captures attention) and (bonus) memorable. The second statement is none of these things!
(2) Relate content to life this week. If, as is often observed, our congregations are "aging", even "elderly", then there is a good chance that most have already heard the theological content of what we have to say. Nothing much is new to older Christians! But what is new is what has been happening in the past seven days: the economic crisis (which is not, by the way, exactly the same as the Great Depression of the 1930s), debate over global warming, concern over ever younger criminals, the Bishop's Walk. Most of our hearers will not have made connections between 'the world of the past week' and 'the Word of God'. If we can make the connection then we will have something 'new' to say.
That might be the difference between attention and slumber during the sermon!!