If you would like to direct the recording session you can join the voice artist, often remotely, while they record your script. This means you can input and make sure you are happy with the final recording.
You can give the voice artist some background about the project, target audience, objective, and where it will be showcased. This information can help the voice artist better understand how to deliver your script.
Additional detail like tone, pace and energy is useful for the voice artist to get this right for you.
To warm up, a run through of the script can be useful to see what works and what doesn’t. In addition recording a number of takes with a different tone/pace can help to choose what will work best.
If you are ever unsure about anything in a script, it is best to record alternate takes which can later be edited. This avoids later re-record parts or the whole script at a cost.