Why slides turn out so bad
Almost every bad presentation has one cause: the slide was made as the speaker's notes, not for the audience.
The text is packed in because the speaker fears forgetting. And when packed text goes on the screen, the audience starts reading and stops listening. Then the speaker reads it aloud, and everyone in the room takes in the same text twice.
The fix is one sheet of paper: keep your notes separate, in front of your own eyes. What goes on the screen is for the audience.
One slide, one idea
This is the main rule, and all the other rules come from it.
If a slide has two ideas, make two slides. Slides are cheap, attention is expensive.
The title itself should say the idea:
Weak: "Sales review"
Good: "Sales doubled in Eid week"
The first says what the slide is about. The second says what the slide proves. If someone reads only the titles, from the second kind of presentation they get the whole story.
How much text
Remember a simple pattern: no more than six lines, and no more than six words per line.
You may feel the ideas will not fit in so little space. They are not meant to. You will say the rest aloud, and that is the reason you are there.
Do not write full sentences, because people read full sentences right through. Write fragments that are completed by what you say.
Text size is at least 24 point. If you have to go smaller than this, the text is too much, and then cut the text instead of shrinking the font.
Which slide to make first
The last one. Write first the one that will come last.
That slide is your real purpose: what people should do or remember after listening. When that is fixed, arranging the other slides becomes easy by itself, because each has one job: to move towards that last idea.
And what does not move that way, drop it, however nice it is.
The structure
In most presentations, this order works:
- Title slide: the topic, your name, the date
- Why this matters: the problem or the chance, on one slide
- The main points, three to five slides, one idea on each
- Proof: numbers, examples or pictures
- So what do we do: the recommendation or the next step
- Thanks and contact
Ten minutes does not need more than ten slides. One slide a minute is a rule of thumb that works, but it is not a rule, it is an estimate.
Charts and pictures
Charts: one message per chart. Colour the part that is the main point and keep the rest grey. Write the conclusion in the title, and write the unit on the axis.
Do not copy a table from a spreadsheet onto a slide. A table is for paper, not for a screen. If you really need a table, mark the cell that is the main point with a different colour.
Pictures: a good picture does half the work of a slide, and a bad picture destroys trust. Avoid blurry pictures, old clip art and stock photos with watermarks.
If you put in a picture, make it big. A small picture in a corner is decoration, not information.
Fonts and colours
No more than two fonts. One for the title, one for everything else. In a Bangla presentation, pick a font that looks clean at a large size, and check the conjunct letters once.
Colours: one main colour, one colour for emphasis, and a white or light background. If the room has a projector, avoid dark backgrounds, because under projector light dark colours turn grey and the text fades.
The most important test is simple: open the slide on your own phone and hold it at arm's length. If it cannot be read that way, it cannot be read from the back row of the room.
The mistakes that happen most
| Mistake | What happens in the room |
| Reading the slide aloud | The audience stops listening |
| Six or seven points on every slide | Nobody can tell which is important |
| Shrinking the font to fit text | It cannot be read from the back |
| A separate animation on every line | Time is wasted, attention breaks |
| A spreadsheet table pasted straight in | Nobody reads it |
| Only "Thank you" on the last slide | The most valuable slide goes empty |
A word about the last one. During questions and answers, the last slide is the one on the screen, often for ten minutes. Instead of "Thank you", put your main point and your contact details there.
If you make slides with AI
The structure and the draft come fast, but three things.
First say who it is for and how many minutes. If you do not say these two, you get a generic deck. If you say "for teachers, ten minutes, and at the end I have to ask for a decision", you get much more useful material.
Give the numbers yourself. If it does not know, numbers that look reasonable may be put in, and in the meeting the questions will be about exactly those. This is the commonest place where AI says wrong things with confidence.
Ask it to cut the text. The first draft usually has too much text. Say "no more than six lines per slide" and run it once more.
In the BanglaCodes chat, in the "More" menu below the writing box, there is a button called Presentation. Write the topic and how many minutes, and the slides are made, and you can download them as a PDF.
How to phrase things well to get a good result is written separately in the rules for writing a good prompt.
If you want to make one yourself, open the presentation page.
Questions and answers
How many slides should a presentation have? Work it out at one a minute, then cut. Around ten for ten minutes. The number is not a rule, but with too many slides each one gets less time and none is remembered.
Should I write the slides in Bangla or English? In the language the audience is comfortable with. Do not mix them, especially inside one slide. Keeping technical words in English and writing the rest in Bangla is natural and that is fine.
Where do I keep my notes? In the notes box below the slide, or on a paper in your hand. Not on the screen. With notes, the fear of forgetting is less, and then you dare to leave the slide empty.
Can I use animation? A little, and of one kind. Bringing in points one by one helps when you do not want the audience to read ahead. Spinning, bouncing or animations with sound do grab attention, but away from what you are saying.
What if the screen is small or the projector is weak? Choose a light background and dark text, and make the font bigger. Avoid thin fonts, because on a weak projector thin letters fade.
Is it good to send a presentation as a PDF? A PDF is safe to send, because the layout stays right even if the other computer does not have the font. But for someone who only has to read, a two page note helps more than slides.
What do I put on the last slide? Your main point in one line, the next step, and your contact. This slide stays on the screen for the whole of the questions and answers, so it is the most seen slide.
Can people tell slides were made with AI? It shows if all the slides have the same mould and each has exactly three points. If you take the draft and put in your own examples and your own numbers, it no longer shows.
In short
- One idea per slide, and the title itself carries that idea
- Six lines, six words per line, font at least 24 point
- Make the last slide first, it is your purpose
- One message per chart, colour the main part, keep the rest grey
- No more than two fonts, a light background for a projector
- Keep notes separate, and you will not be afraid to leave a slide empty
- On the last slide, not "Thank you" but the main point and contact