Your first task is to decide on a topic. You don't have to be the world expert on the topic to be a presenter. Everyone has an experience to share and a observation to make.
Is the session you are proposing ideally suited for a presentation or would it be better as a blog post?
Start with the title and a short 100 word description of the talk.
You are probably going to need this when you submit the talk and it will usually be used in the event program so make sure it sounds interesting. Don't try to write your entire session in the description, that comes later.
Now we can start to build our talk.
I usually write a quick 10 point outline. This gives me the flow of the session and lets me order the key talking points. Don't go into details - this is just an outline - so one or two word bullets is enough.
Fill in the details
This is still not the text of your presentation that comes later - here we are just expanding the outline with further details. I do all of this in a text editor so that it is quick and easy and I tend not to do this in a linear fashion. I complete the details for each part of the outline as they come to me. You will almost certainly find that not everything you write now will make it into the final presentation. Don't worry about that - just write it all down and review it later.
Slides or a speech
This is up to you. Some people prefer to write a complete speech and then create slides to accompany it. Others are happy to use the slides as notes and speak more freely. This is something that is really personal and only you can tell which is the best method for you. The important thing to remember though is that reading words on the page or screen is not the same as hearing them. Personally I almost always skip the speech writing and go right ahead and build slides from my detailed outline, but for your first presentation I would probably recommend writing one.
No one like spoilers - don't start your session with an overview of everything you are going to say.
Do I really need slides?
I hear this one all the time. My talk doesn't need illustrations or examples and I want the audience to concentrate on me without distractions so I don't need slides. Everyone needs some slides - they are the backdrop to your performance - they are the memory aids or takeaways.
So how many slides do I need?
As a general rule I like to work to an average of one slide for every two minutes of the talk. If you can't explain everything on the slide in that time then you have too much on the screen.
Slides accompany your presentation - they are not the complete text - you wan't people to listen not to read.
What about the font?
Two rules - keep it simple and make it big. Funky fonts are for design they are not for readability. You need the audience to be able to read the word f you expect them to remember it. You shouldn't be thinking about how "pretty it looks".
Select a font size that is twice the age of your audience.
A big font ensures everyone can read the text AND stops you from committing the cardinal sin of putting your speech on a slide.
Keep it simple
Keynote and PowerPoint are both very powerful tools you can use to create a slide deck. But with that power comes great responsibility. I work to a very simple template and I hardly ever touch anything more than the image and text buttons. All those fancy transitions, animations and effects might look great on your laptop screen but trust me - no one wants to watch 50 slides with 50 special effects. We all know it's easy to do that with the right software so no one will be impressed.
If you can't trust yourself not to use all the whizzbang features then go for a simpler software solution. There are several presentation tools available online now that force you to concentrate on the message. I'm pretty impressed with Haiku Deck and Bunkr but I am pretty sure there are many others.
Everyone needs to practice - especially if this is your first public presentation. You will be nervous so don't worry about that. My top tip here is to make sure that you really know your first few sentences. This ensures that you start in a positive manner, and once you are into the presentation you won't even notice the nerves any more.
Practice by speaking not reading. Standing not sitting.
Everyone says that they don't like the sound of their own voice. But what about your actions? Do you walk around staring at the floor? Do you fill every pause with fillers like um and ah? Are you repeating the same phrases - "As I said before", "Now we can see", "and finally"? Are you talking too fast?
A simple recording of your presentation using a web cam is enough to highlight these common issues. Practice speaking more slowly than you do in conversation, especially if your audience are not native speakers of your own language. Practice makes perfect or something close to that.
On the day
More accurately this should be called the night before. Don't get drunk!!! Seriously don't get drunk and get a good night's rest. You will thank me in the morning.
Never start a presentation with an apology.
It's your first time so there will be things that you have forgotten or not taken into account. So make sure you are well prepared and not reliant on anything especially an internet connection or battery power. The earlier you can get set up in the presentation room the better. You should be waiting for the audience to arrive - they should not be waiting for you to be ready.
When it all goes wrong
I have lost count of the number of times something has gone wrong during a presentation I have given. It happens to everyone - the trick is for the audience not to know anything at all about it.
Don't say sorry
If you click the next slide and realise you forgot to say something on the previous slide. Say it now. Don't click back. Most people will not even have noticed so there is no point in telling the entire audience. If you spot a typo on your slide the same thing applies - don't point it out to everyone.
Anyone with kids will know about magic water. It is the cure for all ills, bumps and bruises. It has the same magic effect for speakers. If you forget what to say next or lose your train of thought take a break and pour a glass of water. This gives you time to gather your thoughts and no one will ever think anything went wrong.
At the end of every presentation I ask myself - did I enjoy that? If I did, and I almost always do, then that will come across to the audience. They will appreciate the time that you have spent preparing the presentation and most importantly sharing your knowledge. But if you are not enjoying it and don't have fun that will come across as well and be a very boring presentation.
Everyone can speak. Everyone should speak. Don't be afraid.