Start with the space inside the boot shaft and the hem above it. Slim trousers may fit inside knee-high boots; wider trousers usually need to fall outside. Try the combination while sitting and walking before choosing the rest of the outfit.

With slim trousers or leggings, smooth the fabric inside the shaft and close the boot without forcing it. If the fabric bunches or the closure feels tight, change the bottom or the boots. Dark skinny jeans, a loose knit, and flat knee-high boots are one starting combination. Try a wider trouser leg outside the shaft as a separate option. Check that the hem moves freely and does not catch on the boot when you walk. The two arrangements need different trouser widths, so test them with the actual pair.
Choose the skirt length with your boots on:
Key points:
Macaron's personal AI can compare skirt and trouser outfits for your boots using the lengths and layers you describe. Keep the boot shape fixed while trying the alternatives. Sit down in the skirt, stand, and walk once more; the hem should return to a comfortable position without constant adjusting.

Add the warmer knit and coat after the bottom-and-boot combination works. Test the layers together so a bulky sweater does not make the coat uncomfortable. Use the winter outfit examples if you want the boots to join a coat-led or colorful-knit look. Tall fashion boots are not automatically suitable for rain or ice. Choose footwear for the conditions you expect, even if that means changing the outfit. Keep the successful indoor or dry-day combination for another occasion, and note which trousers sat comfortably inside the shaft.
No, the jeans and shaft need to fit comfortably together. Choose slimmer fabric inside the boot or enough trouser width to wear it outside.
Yes, overlapping hems can make a continuous line. Walk in the combination to check that the skirt does not catch.
No, flat boots can work with skirts or dresses. Use the venue, your walking plans, and preferred outline to choose the pair.