“Read it just like you’re talking to someone in conversation”?
In voiceover, it’s a nice plan- but it doesn’t always work.
How many times, in your real life, do you go up to a pal and start an exchange by saying, oh, “Introducing…!”?
Yet, in some narrations, that’s exactly what we are doing – setting up what will soon come (visually or otherwise), and subtly commenting on/closing what has come before. In these cases, we may need to use our “introducing…!” delivery, our our “ta-da!” voice.
When I voice the tracks for live announce shows, for instance, this is a clear choice. The intention is to get attention, and set up what comes next. In movies promos, radio imaging, etc. – sure. same thing – though it still must be sincere within those choices.
In narration, it may be a bit more subtle than promo voice, but your voiceover is still the connective tissue between elements before and after your sentences.
Here’s an example of a narration as connective tissue between elements, courtesy of Action Media.
If possible, it does help to know what those segments are – sometimes the client will provide a description, at least, as part of the script. If not, use your imagination to fill in the gaps. Always, if you can, check out the finished product to see how it all married. This helps next time you do a similar project.