Design at the media size, not at A4
The most expensive habit in outdoor is laying artwork out at a convenient size and scaling it up. Type that looked crisp becomes soft, gradients band, and logos acquire edges.
Set the document at the real size - or at a clean fraction of it, like a tenth - and design there. Everything downstream is easier.
Resolution is about viewing distance, not about a magic number
A hoarding read from forty metres does not need the resolution of a brochure read at forty centimetres. Chasing 300 dpi at hoarding size produces files nobody can open and gains nothing.
What matters is that the file is genuinely at the resolution it claims. An image upscaled in software is not higher resolution; it is the same image with more pixels.
Leave the right bleed for the frame
Outdoor media is mounted, wrapped or framed, and the amount that disappears at the edge varies by structure. Ask what the mounting is before finalising the layout, and keep anything that must be readable well inside the safe area.
One idea survives the drive past
A hoarding is read at speed, at an angle, usually by someone doing something else. What survives is one idea, one image and a name. Everything else is decoration you are paying for by the square metre.
If the layout needs a second sentence to work, it is a leaflet, not a hoarding.
Material and mounting are part of the artwork decision
Flex, vinyl and the finishing that holds them behave differently in sun and rain. A campaign that has to survive a monsoon is specified differently from one that runs for three weeks in winter, and that decision changes what the artwork should be built on.
A short file checklist
Correct document size. Genuine resolution, not upscaled. Fonts outlined or supplied. Bleed appropriate to the mounting. Critical content inside the safe area. Colours specified rather than assumed.
Six lines. They prevent nearly every outdoor reprint we see.
Working out a sensible file size
A practical approach: build the document at one tenth of the finished size and work at 300 dpi there. That produces a file equivalent to 30 dpi at full size, which is ample for something read from tens of metres, and it stays openable.
The important part is that the image content is genuinely that resolution rather than upscaled. Software can add pixels; it cannot add detail that was never captured.
Type sizes that actually work outdoors
Rules of thumb exist for legibility at distance, but the more useful test is physical: print the layout on a sheet of A4, put it on a wall, and walk back until it is the same relative size as the hoarding will be from the road.
If the second line becomes unreadable before you get there, the second line is not doing any work.
Colour outdoors is not colour indoors
Sunlight flattens contrast and shifts perception. Colours that separate nicely on a screen can merge on a board in bright light, and dark type on a mid-tone background is much weaker outdoors than it looks in a proof.
Push contrast further than feels necessary. Outdoor is the one place where a design that looks slightly crude on screen is often correct on site.
What to confirm before artwork starts
The exact finished size, the mounting method, how much is lost at the edges, the viewing distance and direction, and whether the site is lit at night. Five answers, all from the media owner, all cheap to get before design and expensive to discover afterwards.
