Simple

The actual way one must be is simple. But that simple in standard refers to easily understandable. Which is again in pragmatic world if implied based on every other person will lead to a different conclusions and support to initial idea. 

Simply when the more, that you have knowledge about, the sharper becomes, your understanding. As for filling in the holes in the information will be not totally dependent on the speaker but with our former learnings we can efficiently fill them in ourselves; which as a result will seem simple explanation for us. But if the situation is reversed. And we lack such knowledge to fill in the blanks, we get more dependent on the speaker for the information resources and also we have to make effort to understand.

So, the key ends up to be in our childhood method of perceiving things. How first we have a taste of any new thing we come across, don't immediately give up. Then when we have the idea of the sort of thing related to it. If it's necessary for us we make continuous effort to get it to be our own skill we do so. Unless we learn about it very well. 

Hence, to keep things simple we must totally understand the situation or idea we are supporting. Based on which we must make conclusion on purpose for us to utilize the idea. Such that after practice we will be able to present the audience clearly of what we want to present. The disaster roots in when one is unprepared and also unaware of what it is speaking about and nervousness is just natural. You become blank because there was nothing there you actually prepared for.