If you are on your feet all day, the three things that matter are a sole with some cushioning and a bit of thickness, a heel of roughly two to four centimetres rather than none, and a fit that holds your foot without gripping it. Completely flat shoes are often the worst offenders, because a paper-thin sole transmits every pavement and offers the arch nothing at all.

That surprises people, and it is why a low block heel is usually more comfortable over eight hours than a ballet flat. What follows are the three shapes that genuinely work, and what to look for inside them, because from the outside a good version and a punishing version look nearly identical. The tell is almost always the sole.

Below, the three shapes worth standing in: the low heel, the loafer and the flat you can walk in. M.Gemi, ALOHAS, Mansur Gavriel and Tibi feature, and Frēda Salvador gets the Label Love.

A low heel is my first recommendation for a long day, because the height takes pressure off the heel and the width spreads your weight across a stable base. Anything up to about four centimetres is walkable in a way a stiletto never is.

What to check. The heel should sit directly under your heel bone, not set back, since a set-back heel forces your ankle to stabilise all day. Look for a heel that is as wide at the bottom as at the top, or close to it. And check the shoe does not need a strap to stay on, because if it does, the strap will do the gripping. Mules are the risky category here since your foot has to hold them on, so choose one with a snug vamp that covers the joint of your toes. Jenni Kayne and Khaite do the considered versions, Splendid and Cinq À Sept the rest, and M.Gemi's loafer mule is the most secure shape in this grid.

The loafer is the most reliable all-day shoe there is, because it is a closed shoe with a real sole and a structured heel counter, which is the stiff bit at the back that stops your foot sliding around.

Buying notes that matter. Squeeze the heel counter: if it collapses between your fingers, the shoe will not support you. Look for a leather or padded lining rather than raw synthetic, because a full day of friction on an unlined seam is where blisters come from. And check that the shoe flexes at the ball of the foot rather than in the middle of the arch, which is the single best test of whether a sole is any good. Frēda Salvador and Mansur Gavriel are the considered picks, ALOHAS and JW PEI the accessible ones, and Joseph's penny loafers are the best value real-leather pair here.

Not all flats are the same, and the difference is almost entirely the sole. A ballet flat with a 2mm leather sole and no insole is a slipper. A flat with a rubber or stacked leather sole, a slight heel lift and a little padding is a genuinely wearable shoe.

So look at the shoe from the side. If there is no visible sole edge, expect to feel the pavement. Also check the toe box: a very pointed flat concentrates pressure on the outer toes, and a rounded or square toe is far kinder over hours. Elastic at the topline helps a flat stay on without a strap. Mansur Gavriel and Jenni Kayne do the substantial versions, Splendid the cheap and cheerful, and Joseph and Tibi the ones with enough sole to take a full day. Cult Gaia and Ganni are the ones I would buy for how they look and wear for six hours rather than twelve.

Frēda Salvador is the label this issue is built around, because comfort is the design brief rather than an afterthought, and the shoes do not look like it. The house shapes are loafers, mules, flats and boots, mostly on chunky lug or stacked soles, made in Spain.

The practical detail I care about: the lug soles are thick enough to insulate you from pavement, and the mules have a covered vamp so your foot is not doing the work of holding them on. The moccasin boots are the softest thing in the range and the ones I would wear on a travel day. The rain-resistant boot is the only shoe in this whole issue designed for actual weather. Sizing runs slightly narrow through the toe, so take the larger size if you are between two, and know that the lug styles need a few wears before the sole softens.

The shoes on my radar this month.

Ganni feminine buckle ballerinas in red, the colour doing all the work.

Cult Gaia Claire mule in pink multi, the impractical one, honestly.

Faherty Reserve Venetian loafer in chocolate, the softest thing on the list.

Staud Brigitte leather mule, a clean low heel.

ALOHAS Aven loafers in brown, the cheapest thing on the list and a kind toe shape.

Cinq À Sept Remi leather tassel loafer, for a day that turns into an evening.

Jenni Kayne Clara mule, the one I would wear to work weekly.

Tibi Somerset embossed flat, texture instead of a heel.

How I judge a shoe for a long day, in the shop.

Bend it. It should flex at the ball of the foot, not fold in the middle of the arch. This one test rules out most bad shoes.

Squeeze the back. A heel counter that collapses will not support you for eight hours, whatever the sole is like.

Look at the sole edge from the side. No visible sole means you will feel every paving slab.

Walk on a hard floor, not carpet. Shop carpet flatters every shoe in the building.

If you take one thing away: a low block heel with a thick sole will beat a flimsy flat over a long day, every time. Flatness is not comfort. Cushioning, a stable base and a shoe that stays on without gripping are.