One simple rule works for posters: if you cannot tell what it is about from a few steps away, the design needs simplifying. The same principles help with leaflets and catalogue pages, because in every case the eye is looking for somewhere to land.
Guiding the eye
Nobody reads a poster from top to bottom. The largest element registers first, then colour, then a face or movement in a photograph. Smaller text comes last. That order is worth using deliberately.
- One main element - a large headline or a strong image, never both at the same size.
- A clear difference in scale - when everything is medium, nothing pulls attention.
- Contrast - dark lettering on a light background reads best from a distance.
- Empty space - a margin around the headline does more than a frame ever will.
- One practical detail - a date, an address or a web page, rather than all of them.
What to check before printing
The easiest test is to shrink the design to the size of a stamp and look at it at arm's length. Whatever still reads is what a passer-by will see. It is also worth standing a few steps back from the screen to check the headline can be read without effort.
Before sending the file, leave a little spare space at the edges so nothing important vanishes when the sheet is trimmed, and use good photographs rather than pictures pulled off the internet. At a large size every detail shows far more clearly than it does on a phone.