Well, speaking slower is definitely a good thing- I find that when people speak quickly, they seem more nervous. A person who speaks slower seems more deliberate and poised. You might sound like you're hesitating because you prolong the ends of words while you're thinking of the next thing to say instead of stopping entirely and starting again with the next sentence. Perhaps you also add a little inflection at the ends of your sentences, rather than keep them sharp. Not sure if those things accurate, but I know I'm guilty of it. I suppose just practice stopping while you're thinking of the next thing to say; a little silence is okay. You might also be speaking softer than you want to be, which makes your voice breathier and higher pitched than normal. I find that when this happens to me, I feel like I'm speaking "from" my throat, since I feel it in my throat more. So practice speaking in a non-soft tone, and focus on speaking "from" your diaphragm to create a deeper sound, which sounds more confident. Record yourself reading a page from a book, and then summarizing what happened. See how you do from reading, to a simulated conversational piece. Practice switching up your speech patterns to determine which one sounds most acceptable to you, and try to remain cognizant of it in actual conversation. Edit: typos