Designing for newsprint is not designing for a screen
A screen makes colour out of light and holds a pixel exactly where you put it. Newsprint does neither. It is absorbent, uncoated and slightly grey before any ink touches it, and the ink itself spreads into the fibres by a small but visible amount. Every difference between the file you export and the paper you hold comes back to that.
Ink spread, or dot gain, is the first thing to understand. A fine hairline rule that looks elegant at 0.25pt on your monitor will thicken on press and can close up entirely. Small text with delicate serifs fills in around the joints, which is why printers set a minimum body size at all. Newspaper Club puts that floor at 8pt and says some faces manage smaller, which is an honest way of admitting it depends on the typeface as much as the number.
Colour is the second. Newsprint dulls everything, so a saturated brand blue arrives softer and greyer than it left. Working in CMYK from the start means you see roughly what you will get instead of discovering it after the order ships. There is one habit worth adopting immediately: set black text to 100 percent K only, never to a mix of all four inks. A four colour black on a press that shifts by half a millimetre gives you text with coloured fringes, and on newsprint that shift is normal rather than exceptional.
The third difference is the one that surprises people most, and it is why the calculator above leads with the safe area rather than with bleed. Most commercial printing wants bleed, an extra few millimetres of artwork past the trim line so that a colour running to the edge still runs to the edge after cutting. Custom newspaper printers generally do not. MakeMyNewspaper says outright that it does not accept bleeds and wants a half inch of white around every page. Newspaper Club asks for single pages with no crop marks or bleed added. If your instinct from other print work is to add three millimetres and crop marks, that instinct is wrong here.
Where people go wrong, in the order they go wrong
The most common mistake is starting in a template. Canva has thousands of newspaper layouts and almost none of them are built to a real printer's dimensions, because they were drawn to look right on a screen. A design begun in the wrong shape cannot be rescued by resizing at the end: the text reflows, the columns stop lining up, and the photographs crop somewhere you did not choose. Get the trim size from your printer first, type it into a custom size, and start there.
The second is the page count. Newspapers are printed on folded sheets, so pages come in fours, or twos on Newspaper Club's traditional broadsheet. Writing enough copy for a fourteen page paper means ordering sixteen and finding something for the two spare pages, and it is much easier to plan for that than to discover it the night before a deadline. The calculator above will tell you whether a count is legal for the format you picked.
The third is images. A photograph pulled from a phone gallery or a messaging app is often fine on screen and far too small once it is spread across half a broadsheet page. Resolution is only meaningful in relation to printed size, and the arithmetic is not obvious in your head. The DPI checker does it, and more usefully it tells you the largest size an image can go before it drops below the printer's minimum.
The fourth is leaving the margin to chance. Fifteen millimetres feels generous when you are looking at a page on a monitor, so people creep into it with a page number here and a caption there. Presses move. The margin is not decoration, it is the tolerance that keeps your text on the paper.