This is not a question your audience should be asking.
During one of our presentation skills workshops, a participant (let’s call him Harold) described to the group his boss’s rule about hands: If you’re speaking from your seat at a table, keep your hands under the table.
Harold’s demonstration of this technique prompted several in the group to ask, “What are you doing with your hands?” — not exactly what you want your audience to be thinking about. Furthermore, by keeping his hands under the table, Harold became less expressive; his hands were less available to participate in the delivery of his ideas.
So what should you do with your hands? Whether you’re sitting or standing, leave them relaxed and available (not tucked under a table or gripping onto each other). This will allow your hands to respond freely and naturally when you have the impulse to move them.