You may emphasise the general point that preparation is very important, not least because this will help to overcome any nervousness that your friend will feel when he or she makes the presentation. You may also emphasise that she or he should think about the audience and what is it that he or she will want to tell them. You may tell her or him to make sure that the presentation has clear objectives and that it should be kept simple so that there is no danger of overloading the audience with too much information in a short period. This will mean telling the audience what they need to know and eliminating other information. You may also tell him or her that using visual aids will be important but that these should support the key points you wish to make and not be used to show off your technical skills as this may only serve to annoy or confuse your audience. Clear visual aids will also be helpful to your friend in delivering her or his presentation. You may also advise your friend to practise his or her presentation, to invite members of the audience to ask some questions during the actual performance to help to engage them but to remain mindful of the time allowed to complete it.