Dot grid paper, Tabloid
Five millimeter dots across 11 by 17 inches, the US large format, for work that has to be seen whole.
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Tabloid is the US large sheet
Where Europe reaches for A3, North America reaches for Tabloid at 11 by 17 inches, which is slightly wider and slightly shorter. Most office copiers take it, which makes it far easier to get printed than A3 in the US. At 5 mm spacing it holds roughly 1,300 dots across a sheet you can spread on a table and have three people read at once.
Dots handle mixed content better than lines
A large planning sheet usually ends up carrying several kinds of thing at once: boxes, arrows, a small table, a paragraph of notes, a sketch. Ruled lines fight everything that is not writing. Dots give alignment for all of it and then recede. Lighten them further at this size, since at table viewing distance you need much less grid than the page suggests.
Landscape is usually the right orientation
Most large-format planning is wider than it is tall: timelines, org charts, process flows, wireframe sets in a row. Tabloid in landscape gives you 17 inches of width, which is where the format earns its keep. The orientation control is next to the page size in the generator. For the metric equivalent, the A3 sheet is the same idea.
Printing it accurately
This only measures correctly if your printer doesn't rescale the page. In the print dialog set Scale: 100%, not "Fit to page" or "Shrink oversized pages". If you're not sure it worked, print the calibration page, measure the ruler on it with a real ruler, and it will tell you exactly what your printer is doing to the page.