Today a lovely fellow who usually does a radio show, but in this time of freely and joyfully given creativity, asked me if I had any tips on how to read an audiobook.  (audiobooks are markedly different from radio)  ...and off the top of my head, here were my answers:

1. I think the two most critical things, and absolutely the most difficult, are 1) slow down  1a) slow down more  1b) ..eeeven more

  and

2. don't be afraid to leave sPACE!

on radio space is DEAD AIR - BAD

in audiobooks space is EMOTION

space allows the listener to really hear what was said - if the line was funny, if the line was a gut punch - space is where the listener's imagination takes over

(that said, there are times when zero space is the funniest thing you can do - but that is something that is almost certainly part of your radio repertoir!)

3.  The third thing that I would have told myself is, vary rate of delivery - vary the speed of the prose, based on the emotional roller coaster of the prose.

This is remarkably hard to do for some reason.  i mean, it's easy to slow down as you reach the end of a sentence - but varying the rate of speed in a paragraph?  that's not how we normally speak.

Variation of pace in the right places really ups the impact of the words.

4.  And kinda the last thing I'd put in the "OH GOD I WISH I'D KNOWN THIS" category, is vary the pitch of your delivery, ESPECIALLY the pitch at the end of sentences as pitch tends to fall naturally.  Don't be afraid to let a sentence resolve all the way to the bottom of a declarative sentence!  Whole paragraphs that go by with each sentence-conclusion being a soft, non-commital, semi-tone are incredibly boring - the audience tunes out.

[as a coda I concluded:]  People tend to get too focused on 'voicing' - creating a specific voice for each character - you don't need that nearly as much as allowing emotional cues to creep in - a breath-catch, a hesitation or stumbling, a clipped delivery, a soft one.... you do this kind of thing, and you don't need to 'voice' characters at all.

I hoped this helps him give a lovely reading of the book he's about to embark on!  May fortune favor your work :)