Most first orders are planned around a total unit count. The number that actually determines sell-through is how those units are divided — by size, by colour, and by style.
Start from the size curve, not the total
Write out your expected sales by size before you decide quantities. If you have no history, use the shape of your market: a streetwear drop skews differently from a uniform programme, and a unisex fit sells differently from a women’s cut. The curve matters more than the precision — a plausible curve beats an even split every time.
Avoid the flat split trap
Equal quantities per size feels fair and almost always leaves the extremes behind. Sizes at the edges of the curve should be ordered in smaller quantities, even if that means a slightly higher unit cost at the low end.
Colour: one hero, one support, one test
Three colourways is a workable first range: one that carries the campaign, one that supports it, and one that tests demand. Splitting the same total evenly across five colours usually produces three sell-outs and two leftovers.
Respect the minimum per colourway
Fabric is dyed by colour, so each colourway carries its own minimum. Adding a colour is not free — it consumes part of the order quantity and adds a dye lot. Plan colour count against the minimum, not against the budget alone.
Plan the reorder before the first order
Decide now which style and colour you would reorder, and how quickly. A reorder is faster when the pattern, fabric and colour record are already approved. If a style is likely to reorder, keep its fabric and trim choices simple so a second run does not need new approvals.
The practical version
Choose one fit, two or three colourways, and a size curve that reflects your market. Ship, measure sell-through by size and colour, then plan the second order from data instead of instinct. That is a faster route to a working range than a large first buy split too thin to learn from.