Get the feet right. Then put the body on the feet. Then put the breath in the body. Then speak.
One of the things we try to do as actors is centre ourselves. Centre our voice. All this means is that everything is acting together. In theatre we describe is as being centred. All the movements of the body including twitches of the toes, fingers, breath, mouth, eyes etc are connected through the centre. The centre being an imagined point somewhere below the tummy button. That is all it means. But it's a powerful concept, a sort of magical concepts, and it can be quite scary when someone is saying "you're not centred..." etc.
In real life we are mostly centred, most of the time. (In some senses in real life you cannot be uncentred because you are you, you are life, and the actor's job is to copy you, not the other way round!). So what's so difficult about it? Well performing isn't real life. Everything about performing throws you "off centre". In real life we stand on our feet, breathe with our chest and we say words. But in performance we start with text, and it all goes the other way: you find that you are standing on the words, fitting breaths in between them with the chest and speaking with your feet and hands.
If you are on a 3 man puppet you will have a head and a hand, a bum and a hand, or two feet. Often people look at the hand holding the hands and the feet and move them around. This is an error. The important part of the puppet is the midline - the centre. Look at the head. Look at the bum. Look at the space between the feet. Heads look at things, bums feel things, feet are for standing on. The hands and feet themselves move around this midline. From the centre.
An odd thing I discovered when doing The Table recently, is that even though I don't perform the body or the legs where the centre is, my voice is centred when the puppet is centred. It changes. It relaxes, becomes richer.