Learn your talk as a bullet list not as a script. Know each slide and what it means: which bullet points it matches. Assume that you will ad-lib on the day. Put

Learn your talk as a bullet list not as a script. Know each slide and what it means: which bullet points it matches. Assume that you will ad-lib on the day. Put as little of the real text as you can into the slides themselves. Never read anything: not even a quote. Have a go at doing your slides backwards (or at least your main slides if you tend to have lots of slides per topic). Be sure that you are making a clear message at the end. Then have a go midway (pulp fiction style). Your message should still be clear. You are fully prepared when you can click through your slides while (mostly) looking forward.