Do not sit down and try to manufacture a speech in say in thirty minutes ,  A speech can't be cooked to order like a steak.A speech must grow , select your topic well in advance of speaking date , think over it during odd moments , brood over it , sleep over it , dream over it. Discuss with friends. make it topic of conversation.ask yourself all possible questions concerning it. put down on pieces of paper all thoughts and illustrations that come to you and keep reaching out for more. Ideas , Suggestions, Illustrations will come drifting to you at sundry times - when you are bathing , when you are driving down town , when you are cooking dinner. It has been method of almost all successful speakers.

~  From Dale Carnegie