Some useful tips that I used was having the mark scheme while I was planning the presentation which was useful as the presentation assesses AO4, which is about evaluation, so remember to talk about your strengths, weaknesses, any obstacles/setbacks you faced and how you overcame them and what you would do next time, that should get you full marks in that section. Remember to include any techniques that you used (making a timetable etc.) or any interesting sources which you could talk about as your strengths.
Project Aims are also good. Stating your findings/conclusions are also essential on the mark scheme, but keep this brief as it should be a lot more focused on your journey to discover those findings/conclusions to get full marks.
I recommend plain and simple PowerPoint presentations with minimal slides with barely anymore than 10 words on each slide/2 pictures, the audience should not be distracted by it.
I personally did not use any flashcards, I just loosely improvised but if you are going to have flashcards, keep them brief and do NOT have a script in front of you.
Maintain eye contact and good body language (open posture, hand gestures), speak clearly and confidently.
You MUST make sure you know your topic well because there should be questions from the audience at the end.
I just finished my EPQ on cystic fibrosis and got 50/50 (A*), most of this was from looking at the mark scheme the whole time.
Good luck!