If something that you need to present is not clear, don't leave your audience to solve the puzzle but offer various ways to make it clear.
You may use the following strategy during your presentation about the complex or difficult to understand topic:
1) announce that the topic is like a puzzle and not easy to understand at first look
This will support in getting the right focus from your audience.
2) provide the big picture of the matter / puzzle
This will support the people who need to see the end / bigger picture before the details to get an understanding of the matter
3) present the details of the matter in an organized manner
4) provide examples to clarify the matter and provide perspectives / thought process
5) check back with your audience to see if understood, for example by asking probing questions and look at body language
6) summarize the topic again at the end, allowing for questions
7) wrap-up by mentioning the key takeaway and reference to further information.
With the above you should have covered the topic at least three time in different manners. This is one of the best ways to present a difficult topic for your audience and resolve the puzzle / complex manner for your audience. By means of this you will make a memorable impact.
