Perhaps you are preaching a series of messages on a book of the Bible. Perhaps you are one of several preachers preaching such a series. So naturally you take the first passage of the text and study it to the best of your ability, Sunday comes and you preach it. Next week you give your efforts to the next passage in the book. This is how to preach error in a series.
It seems obvious, but in the busy schedule of ministry, it is so easy to forget. A passage has to be studied in its context. You may misrepresent the author’s intent in chapter 1 if you have not studied chapter 1 in its relation to the other three chapters.
Practically this means finding ways to do as much of the exegetical work as possible, in the whole book, before you preach message one. If you are only preaching one message in the series, then necessarily your broader study will not be to the same level as the passage you are preaching (but perhaps this should push us in the direction of some study in teams whenever possible in multi-preacher series?) If you are preaching the whole series, this macro view of the whole will benefit every individual message and be a blessing to your soul.
If the passages are connected to each other, as each series in a book surely is, then you cannot afford to prepare only one message and then preach it. That’s how to preach error.