[header] How to give a speech without preparation [title] Tell a story you know well. [step] Speeches don't have to be invented from scratch. Telling a personal story is a great way to come up with something quickly: since you already know what happened, you'll know what to say. 
For example : [substeps] At a wedding, you could tell a funny story about growing up with the bride or groom. At a funeral, you could tell a story about how kind or generous the deceased was, or about how they influenced you.