How do you practise/improve recording your voice and avoid getting frustrated?

So, by far my biggest pain point is that I am not a professional voice actor, and therefore I slur my speech, swallow up words, speak too fast, pronounce things weirdly every now and then etc. and it makes the whole voice over recording process very frustrating. I end up having to re-record the same segment sometimes 10+ times and it slows everything down like crazy. It also breaks my train of thought since I am constantly switching between focusing on what to say, and focusing on how it sounds.

I figure this must be at least to some degree a universal problem for anyone who has to use their voice to produce something.

Obviously, an easy answer to this problem is to just let go of perfectionism, go with more or less your first take (what most aspiring channels seem to do) and perhaps that's what I should be doing as well. But I wonder, have any of you found any exercises or other ways to practice and improve the quality of your speech in order to speed up the recording process when it includes your voice?