I absolutely hated public speaking but I found a few things helped my nerves,
* First remember everyone else is in the same boat. Unless you have a particularly evil class I should think they'd understand, and many feel the same.
* Perhaps sit comfortably so you're not shuffling around, perhaps by the computer or board so you can work the slideshow.
* Note-wise keep it to a minimum, perhaps just summarising each slide. Subtle jokes could work, and loosen everyone up a little. No-one likes a presentation fully read to them.
* Lastly, make sure your notes are prepared in advance and know when you're timing your slides etc for to ensure it goes smoothly.
Hope this helps, good luck! Loradora68 xxx