I assume that you're presenting with a slideshow behind you. In this case, my best tip would be to not use index cards or notes. It's really easy to get caught up in reading the cards and lose your flow while speaking. Instead, if you think you're going to forget an important detail, add it to the slides. A detail that is important enough to remember without fail is definitely important enough to be written in your slideshow. You could even make subtitle slides to remind you to transition to the next sections. Transforming my presentation to be my index cards really helped me present better, so I hope you can find it helpful, too!
