A quick list of stuff (not) to do in presentations
Disclaimer:
Like everything else that I write, I don't claim any special
knowledge, or indeed any knowledge at all of the things I write about.
They may be completely foundationless rubbish. They probably are! On
the other hand, since most of these things are based on my own
reactions to god-awful presentations or just things that I've seen
done badly (possibly by myself), so maybe there is something to them.
Other info
An excellent and amusing document is Till Tandau's extensive documentation
for his Beamer LaTeX class. As well as entertainingly describing the superb
Beamer package, this contains much excellent information on giving good
presentations. See < href="http://latex-beamer.sourceforge.net">the Beamer
web page for more details.
Another good collection of info to bear in mind, though not presentation
specific is the World Wide Web Consortium (W3C) info on accessibility
of information. It's linked to from www.w3.org.
How to make the slides?
Methods for preparing presentations include: OpenOffice Impress,
MS PowerPoint, LaTeX (Beamer, Prosper, FoilTeX...), HTML, Inkscape or other SVG
editor, DocBook... and there's always pen and acetate / chalk and talk etc., though
they're less useful since your listeners only get one chance to see your talk.
Personally, I find the compactness and programmability of LaTeX: despite a
brief deviation into OpenOffice when I got fed up with FoilTeX, I'm now
happy to be back in LaTeX and using Beamer. For non-technical talks,
perhaps OpenOffice or similar are better: it's hard in LaTeX to put images
in random places, use silly fonts or to overlay arrows and things in confusing
ways. Actually, I think those probably count as features rather than
limitations.
The list
And with that it's time for the big, not very coherent list of things
to bear in mind:
-
First things first — tailor the talk length to the time you've been
allocated. A good rule of thumb is to have around one slide per minute —
this will focus the talk on the important aspects and give you time to explain
properly what you're talking about. This doesn't mean you should stuff as much
tiny text into each page as possible: lay it out spaciously and just talk
about the important bits rather than all the little details. Thanks to Amber
Jenkins for reminding me of this one :-)
-
Use a white background and san-serif text. It's at least as attractive as
gradient backgrounds with funky "Wordart" shaded text if you design it
nicely (ask Apple's advertising agent) and everyone will be able to
read it easily. If black text on a white backdrop is too stark, try using a
dark grey or blue text instead --- this helps to anti-alias the text against
the background and make it more readable. Equally make sure that your text
does stand out from the background: common errors are "red on navy" and
"LaTeX-green/yellow on white". Judicious use of colour highlights through
the text will mean it still ends up looking pretty!
-
Don't fill your slides full of large paragraphs of text --- cut them down to
minimal points and then elaborate on them when you speak. I'm very bad at this one
since I want my talks to be readable by people who aren't necessarily there at the
time, but I've found that writing the slides as prose first and then cutting
them down to "bullet point" statements helps to focus the talk anyway.
-
Despite the first point above, if you've got a lot of material, don't try
and force it on to a small number of slides with small text. Use more slides and
large fonts instead: > 20 pt is a fairly sensible size. If you've got that much to
talk about, make sure you've been allocated a sensible amount of time. If not,
cut your talk down to size... or ask in advance for a longer slot.
-
Don't use yellow or bright green text on white backdrops. If you're using
LaTeX then redefine the default green to something a bit darker before
using it!
-
Use error bars whenever possible on plots. This is more a physics issue
than a presentation one, but without error estimates the results are a bit
meaningless. If you don't have error bars, make a comment about the errors
in the text.
-
Put titles on graphs, declare what they are (and if possible what their
characteristic shape means) and label the axes carefully.
-
Put all that you want to say on the slides: people will often want to
reference your talk afterwards, so make sure it is a good reference for all
the important points that you make. For the same reason, think twice before
using animation effects...when printed out, none of the points made by the
animation will still work. A good diagram is better than a flashy
animation.
-
Put your name, the date, the meeting and the slide number on each slide:
again this is useful for later reference.
-
If the talk is to be downloadable later, make the filename contain the
details of your talk: date, meeting, subject and your name are all useful
info to put in the filename. Join them together with hyphens and
underscores, rather than spaces, this way you won't end up with filesystem
problems.
-
Define acronyms. This is always a good idea.
-
Be careful with your choice of fonts: don't just use things on your
machine that will not be generically available. If the computer from which
you present your talk (or on to which a reader downloads your talk) doesn't
have the required obscure font then your slides may be reduced to gibberish.
Arial, Helvetica and Times fonts are very professionally designed and will
work pretty much anywhere. Of course, you avoid this problem by writing your
presentation to file with embedded fonts, as can be done with e.g. PDFs —
this can be set in an options menu if you're using Acrobat to do the
conversion. Presentations written in TeX/LaTeX don't usually suffer from
this problem since (I believe)
dvips embeds font metrics in the
PostScript file. As far as I know PowerPoint doesn't allow direct embedding
of fonts for security reasons, though I'm not familiar with the program.
-
Don't rely on animation to present information: the printed and stored
versions will not contain your results. This is mostly a nasty side-effect
of PowerPoint presentations — be careful that your presentation remains
useful and accessible as you add more bells and whistles like this. In
particular, animated overlays which sequentially layer on top of other
information will only end up showing the top layer when printed. The same
goes for PDF or PostScript copies generated from the e.g. PowerPoint
originals, for example those generated when you upload a presentation to the
CERN document server. Bear in mind that this can backfire on you if the PC
from which you give your talk doesn't have PowerPoint — this is
guaranteed on Linux systems, for example.
-
If you present photos, take the photo with the subject mounted on a white
backdrop. That way the audience will be able to see it more clearly. It also
looks more "professional" or "slick" if your photo background merges
neatly with the slide background!
-
I have a personal dislike of "overview" sections in talks less than an
hour long: my pet hate is the inclusion of "Summary" in the
overview! Maybe this is just a personal thing, but breaking from the
textbook format can be a good idea, sometimes!
-
When quoting numerical figures from your slides, be sensible about the
number of significant figures you read out. Aside from the technical concern
of not quoting to less than the uncertainty, there's a listenability issue:
your point will be made much better by quoting "6157892 events" as "just
over 6 million events" or "6.2 million events" than it will if you insist
on quoting down to the last digit. You can keep the data on the slide to
full accuracy if you want, but your rôle in explaining the slide contents
will benefit from a more human approach!
That's all for now. Did I get it all wrong? Do you have better ideas? If so, email
me (see www.insectnation.org for the
address and latest version of this document).