If a wash is not doing enough after a month, the next step is a leave-on product. It sits on your skin for hours instead of seconds, so it does noticeably more for bumps and rough patches.

The INKEY List's Glycolic Acid Exfoliating Body Stick is my favorite format. It is seven percent glycolic acid with salicylic acid in a stick you swipe over the backs of your arms, ingrown hairs or bumpy thighs, with no mess on your hands. Soft Services' Smoothing Solution is a leave-on AHA gel made for KP, strawberry skin and ingrown hairs, and Topicals' Slather serum combines lactic and glycolic acids with urea and retinol for really rough, flaky patches.

For breakouts on your back or shoulders, Murad's Clarifying Body Spray pairs salicylic acid with glycolic acid, and the spray reaches places your hands do not. The Ordinary's Salicylic Acid 0.5% Body Serum is simpler and lighter, good for bumpy texture and body breakouts.

If you want something that feels more like a regular body lotion, Glow Recipe's Watermelon Glow body cream uses hibiscus AHA and hyaluronic acid, light and quick to dry down. The INKEY List's PHA body water cream is the gentlest here, three percent PHA that hydrates and exfoliates at once. U Beauty's SCULPT Arm serum is made to smooth and firm the look of upper arms.

Use one leave-on product at a time, not three, and never right after shaving. Put it on at night, on dry skin, so it has hours to work while you sleep and nothing rubs it off.

Chemical exfoliation does the steady work. A scrub is the weekly polish, the thing you do on a Sunday before a dress with bare arms or the first warm weekend of the year.

First Aid Beauty's KP Bump Eraser combines pumice beads with glycolic and lactic acids, made for keratosis pilaris, and it is the one I would pick if bumps are your main complaint. Youth To The People's AHA scrub uses a 10% blend of glycolic, lactic and mandelic acids with physical exfoliants for rough texture.

Sugar scrubs are gentler and leave skin soft. Josie Maran's argan oil and sugar balm scrubs are rich and moisturizing, and they come in Topless Tangerine, bright and citrusy, and a warm vanilla version. Sol de Janeiro's Bum Bum scrub uses crushed cupuaçu seeds and sugar crystals, soft as sand. AKT London's foaming scrub lathers up as it buffs, a nice middle ground if you dislike oily scrubs.

Topicals makes two bars that are easy to keep in the shower. The Faded bar brightens and fades the look of dark spots and uneven tone, and the Slather bar pairs gentle physical and chemical exfoliants for bumpy, textured skin.

Scrub with light pressure, never hard. Your skin should feel smooth and warm afterward, not stinging, and a scrub once or twice a week is plenty alongside an acid. More is not better here, and over-scrubbed skin gets rougher, not smoother. On acid days, skip the scrub entirely and let one method do the work.

AHAs make skin more sensitive to the sun, including the skin on your arms and legs, so any glycolic routine needs sunscreen on whatever you are exfoliating. That part is easy to forget in shorts season.

Start slowly, a few times a week, and build up to daily if your skin is happy. Moisturize right after the shower while your skin is still damp. Skip acids on freshly shaved or broken skin, and give it a month before you judge. Rough patches do not smooth out overnight, but by week four you should notice your arms feel different under your hand.