In the bottom of my office drawer I just found a small card with personalised suggestions for better presenting that I had to fill out after a communication training at McKinsey all the way back in 1996. All the usual things are there: stance, eye contact, etc.
But one things stands out and is so 1996/McKinsey: “Introduce the slide before putting it up” (remember we were still in the time of the overhead projector). McKinsey slides were incredibly busy and filled with data, so plopping that overhead sheet on the projector without warning would overwhelm the audience.
Instead, we had to introduce the message of the slide, show it, talk people through the various elements of the slide (what is on the axes, what the line means, etc. etc.), and maybe repeat the key point one more time.
Now 16 years later, my approach has completely changed. When you put up a slide, it should be completely self explanatory, cutting out unnecessary clutter and spreading out content of multiple slides if needed.