Designing clear slides: layouts, text, colour, images, charts and the design rules professionals use

We've all sat through presentations with walls of tiny text, clashing colours and blurry clip art. Good slides do the opposite: they make your message instantly clear, support what you say, and make you look professional, whether you're presenting a school project, pitching to investors, training staff or reporting to a board. This unit teaches the principles and the PowerPoint/Google Slides tools to design clear, attractive slides.

What slides are for

Slides are visual support for a spoken message. The audience should listen to you and glance at the slides to understand or remember a point. If slides contain everything you say, people read instead of listening (and you might as well send a document).

Plan before you design

1. Audience: who are they, what do they know, what do they care about?
2. Main message: if they remember one sentence, what is it?
3. Structure: introduction (why it matters) → 3–5 key points → conclusion and call to action.
4. Storyboard: sketch slides on paper or write slide titles first (in PowerPoint's Outline View: View → Outline).

A common business structure: Problem → Solution → Evidence → Plan → Ask.

Themes, layouts and the slide master

Themes

Design → Themes apply a coordinated set of colours, fonts and backgrounds. Choose a simple theme; you can change colours (Design → Variants → Colors) and fonts (Variants → Fonts) to match a brand.

Layouts

Each slide uses a layout (Home → Layout): Title Slide, Title and Content, Section Header, Two Content, Comparison, Picture with Caption, Blank. Using layouts (instead of random text boxes) keeps titles in the same place on every slide and makes slides accessible to screen readers.

Slide Master

View → Slide Master controls the design of all layouts: fonts, colours, logo, footer, background. Change it once (e.g. add the company logo bottom-right, set title font), and every slide updates. Close Master View when done.

Google Slides: Slide → Edit theme (similar master editing).

Typography

• Use one or two fonts (e.g. a bold sans-serif for titles and a clean sans-serif for text).
• Sans-serif fonts (Calibri, Arial, Segoe UI, Montserrat) read well on screens.
• Avoid ALL CAPS paragraphs and decorative fonts.
• Left-align body text; centre only titles or short statements.

Less text

The "6×6 rule" (a guideline): no more than about 6 bullets per slide and about 6 words per bullet. Better still: one key sentence and a visual.

Write slide titles as messages: "Mobile orders doubled after the M-Pesa button" beats "Sales data".

Colour and contrast

• High contrast: dark text on a light background, or light text on a dark background. Avoid light grey on white or text over busy photos.
• Limited palette: 2–3 colours plus neutrals; use your brand or the theme's colours.
• One accent colour to highlight what matters (a key number, the best bar in a chart).
• Projectors wash out colours: test in the room if possible; dark text on light backgrounds is safest in bright rooms.
• Colour meaning: green for positive, red for negative/warnings (but don't rely on colour alone, for colour-blind viewers).

Images and icons

• Use relevant, high-quality images; avoid stretched (distorted) or pixelated pictures. Hold Shift while resizing to keep proportions.
• Full-bleed images (covering the whole slide) with a short overlaid statement are powerful; add a dark transparent rectangle behind text for readability.
• Icons (Insert → Icons in Microsoft 365) explain ideas simply and consistently.
• Crop to focus (Picture Format → Crop); Remove Background for product photos.
• Use images you have rights to: your own photos, licensed stock, free sites (Unsplash, Pexels) or PowerPoint's stock images.
• Compress pictures (Picture Format → Compress Pictures) to keep files small for emailing.

Visual hierarchy and layout

Guide the eye to what matters first:

• Size: the most important element is biggest.
• Position: people read top-left to bottom-right.
• Contrast/colour: highlight one thing.
• White space: empty space makes slides calm and focused.

Alignment and spacing

• Use Smart Guides (dotted lines appear when objects line up) and Arrange → Align (left, centre, distribute horizontally) for neat layouts.
• Keep consistent margins; don't put things right at the edge.
• Group objects (Ctrl+G) that belong together.

Designer / Design Ideas

In Microsoft 365, Design → Designer suggests professional layouts when you add pictures or lists. Google Slides has "Explore" suggestions in some versions. Use them as a starting point, then simplify.

Data on slides

• Show one key point per chart; title the slide with that point.
• Choose the right chart: column/bar for comparisons, line for trends, pie only for a few parts (see the Excel charts lesson).
• Simplify: remove gridlines, unnecessary legends and 3D effects; label values directly.
• Highlight the important bar/line in an accent colour, grey for the rest.
• Avoid big tables: show the 3–5 most important numbers, or put the full table in a handout.
• Insert → Chart in PowerPoint (edits in an Excel sheet), or paste a chart from Excel (Paste Options: keep source formatting, or link data so it updates).

Think about it: A slide shows a 12-column table of monthly sales for 8 branches in 10-point text, titled "Branch performance". How could you redesign it?Show answer

Decide the key message (e.g. "Thika overtook Ruiru as our top branch in Q3"), make that the title, and show a simple bar or line chart of just the relevant branches/quarter with Thika highlighted. Move the full table to a handout or appendix slide.

Consistency checklist

• [ ] Same theme, fonts and colours throughout
• [ ] Titles in the same place (using layouts)
• [ ] Bullets and alignment consistent
• [ ] Images similar in style (all photos or all illustrations)
• [ ] Logo/footer from the Slide Master
• [ ] Slide numbers (Insert → Slide Number) for Q&A references

Accessibility

• Use slide layouts with real titles (screen readers use them).
• Add alt text to images (right-click → View Alt Text).
• Ensure contrast and large fonts.
• Don't rely on colour alone.
• Use Review → Check Accessibility (PowerPoint) to find problems.
• Provide captions for videos.

Practice tasks

1. Take a text-heavy slide and redesign it with one message title, 3 short bullets and an image.
2. Use the Slide Master to add a logo and footer to all slides.
3. Create a chart slide where the title states the insight and one bar is highlighted.
4. Build a 7-slide deck using Problem → Solution → Evidence → Plan → Ask.
5. Run Check Accessibility and fix the issues.

Summary

• Slides support your talk; details go in notes and handouts.
• Plan audience, message and structure before designing.
• Use themes, layouts and the Slide Master for consistency.
• Large, simple text (titles 32+ pt, body 20+ pt); few words; message titles.
• High contrast, limited colours, one accent; quality images and icons; white space and alignment.
• Simplify charts and highlight the key point; avoid big tables.
• Check accessibility: layouts, alt text, contrast.

Check yourself

1. Which view controls the design of all slides at once? (two words)

   Show answer

   Slide Master

2. What minimum font size is recommended for body text on slides? Write in pt.

   Show answer

   18

3. What does the 6x6 guideline limit? (one word: bullets and ...)

   Show answer

   words

4. Where should detailed information go instead of on the slide? (two words)

   Show answer

   speaker notes

5. Which key do you hold while resizing an image to keep its proportions?

   Show answer

   Shift

6. What should a slide title state, according to this lesson? (one word: the main ...)

   Show answer

   message

7. Which PowerPoint feature checks for accessibility problems? (two words: Check ...)

   Show answer

   Check Accessibility