Graphic design basics: what designers do, the elements and principles of design, file types, sizes and print vs screen

Graphic design is communicating ideas visually: a poster for a church fundraiser, a logo for a new salon, an Instagram post announcing a sale, a restaurant menu, a business card, packaging for honey jars, a school prospectus, an event banner. Every business needs designs, which is why graphic design is one of the most accessible ways to earn, locally (printing shops, SMEs, churches, schools, politicians, events) and online (Fiverr, Upwork, 99designs, social media clients).

You don't need expensive software to start: Canva (free) on a phone or laptop is enough to produce professional work once you understand the fundamentals in this unit.

What graphic designers do

Tools

Start with Canva and Photopea/Inkscape; move to Adobe or Affinity tools as you grow. Avoid cracked software: it's illegal and often contains malware.

The elements of design

The principles of design

The most common beginner mistakes: too many fonts, too much text, no clear focal point, low contrast, and cramming every space.

The design process

1. Brief: what's it for, who's the audience, what's the message, what's the call to action, sizes and deadline, brand colours/logo, budget.
2. Research: competitors, inspiration (Pinterest, Behance, Dribbble), audience preferences.
3. Sketch/concepts: quick ideas on paper or rough layouts.
4. Design: build the design with hierarchy and brand consistency.
5. Review: check spelling (names, dates, phone numbers!), contrast, alignment.
6. Feedback and revisions: agree on the number of revision rounds in advance.
7. Deliver: correct file formats and sizes for print or digital use.

A simple brief template:

Client: Grace Bakery, Nakuru
Project: Instagram post + A4 poster for a Christmas cake promo
Audience: families in Nakuru, 25–50
Key message: "Order Christmas cakes by 20 Dec – 15% off"
Must include: logo, WhatsApp 07xx..., photo of cake, prices
Style: warm, festive, brand colours (maroon + gold)
Sizes: 1080×1350 px (IG), A4 print (with 3 mm bleed)
Deadline: Friday 5 pm

Raster vs vector

Logos should always be created as vectors so they work on business cards and billboards alike.

File formats

Size, resolution and DPI

• Screens measure in pixels: an Instagram portrait post is 1080×1350 px.
• Print measures in physical size and DPI (dots per inch): print at 300 DPI for sharp results. An A4 poster (210×297 mm) at 300 DPI needs about 2480×3508 px.

def pixels_for_print(width_mm, height_mm, dpi=300):
    inch = 25.4
    return round(width_mm / inch * dpi), round(height_mm / inch * dpi)

for name, w, h in [("Business card (85x55 mm)", 85, 55), ("A5 flyer", 148, 210), ("A4 poster", 210, 297), ("A3 poster", 297, 420)]:
    print(f"{name:26} needs about {pixels_for_print(w, h)} px at 300 DPI")

A low-resolution image (e.g. a 600 px WhatsApp photo) will look blurry when printed large; ask clients for original high-resolution photos.

Print vs screen

Bright RGB colours (neon greens, vivid blues) may print duller in CMYK. Ask the printer for their requirements and, for important jobs, a test print.

Copyright and images

• Don't copy images from Google or other designers' work; it may be copyrighted.
• Use your own photos, client-provided images, or free licensed sources: Unsplash, Pexels, Pixabay (check licences), Canva's library within its licence terms.
• Fonts have licences too; Google Fonts are free for commercial use.
• Don't use famous brands' logos or celebrities' photos in ads without permission.

Summary

• Graphic design communicates visually across branding, marketing, social media, print, packaging and digital work.
• Start with Canva and free tools (Photopea, GIMP, Inkscape); avoid cracked software.
• Use the elements (line, shape, colour, texture, space, form, type) and principles (hierarchy, contrast, alignment, balance, proximity, repetition, white space).
• Follow a process: brief, research, concepts, design, review, revisions, delivery.
• Know raster vs vector, file formats, pixels vs 300 DPI, RGB vs CMYK, bleed and safe zones, and respect copyright.