When you are preparing your presentation, one of the most under-explored areas is to research the location, the venue where you will be giving the presentation.
I once did a presentation at BNI Dynamo in Glasgow, where I was at a podium at one end of the room, then there was a large space, then a huge long table and finally the audience. Horrible. I had to work quick and smart to deliver a presentation that was going to still impact an audience so far removed from the speaker.
When you are going to give a presentation, wherever possible, get to the venue nice and early and check it out. That's the best way to address any issues in the venue that might affect the effectiveness of your speech.
At a recent public speaking course for a Scottish distillery, I stage managed the venue for my clients so that they had their fellow course mates were closest to them, their bosses and co-workers were in the middle distance and I put my bag and laptop at the end of the conference table to make sure no one sat there. I sat where they could see me for reassurance, but not so close that they felt judged during the presentations.
If you can position your audience, then you can take advantage of particular position. At an event in London several years ago, I knew that I was going to have double the people we were expecting. So I moved myself closer to the audience so they were around me in a semi-circle. They felt close and I felt that I could reach out and speak to them personally.
If you will be using a microphone, or projector, then getting there early will allow you to try things out. Take a look at where you can keep your water, where will you place your notes, or index cards.
Get a sense of the relationship between your audience, the projector and you. Ideally, you want to be in a position to gesture to it but without having to turn your back on the audience.
Ideally, if you can watch someone else delivering a speech in that venue before hand, you'll learn a lot about what works and what doesn't in that particular venue.
Having scoped out the venue, you will feel confident that you have controlled any rogue elements and started using the venue to your advantage.