Vivid color does not fail because the dye was weak. It fades because it gets washed out, usually by hot water and the wrong shampoo. So the bottle in the shower matters as much as the jar in the bowl.

Look for gentle, hydrating formulas and wash less often than you would like. Pureology's Nanoworks Gold Hydrating Shampoo is the hydrating pick, and Moroccanoil's Hydrating Shampoo with Argan Oil is the gentle everyday one. Kérastase's Première Repairing Shampoo and Oribe's Gold Lust Repair and Restore are the repair-minded choices for damaged, lightened hair. OUAI's Fine Hair Shampoo is the one to try if your strands are thin and go limp fast. amika's Big Hit Volumizing Shampoo is the volumizing option.

Wash with lukewarm water, rinse the last minute of the shower cooler, and apply shampoo mostly at the scalp. Let the suds run down the lengths instead of scrubbing them. The first few washes matter most. Pinks tend to fade sooner, while blues and greens can linger, so plan your washes around that.

A small test: after a wash, look at the water. If it runs bright, use cooler water and less shampoo the next time. If it runs clear, you are doing well.

Color that has been dyed will always look a little duller than a fresh bowl of it, but a good gloss can close the gap. Glosses smooth the hair surface so it reflects light, and masks put back the softness that bleaching and dyeing take away.

Gisou's Honey Gloss Hydrating Hair Mask is the one I would use weekly, a hydrating mask for dry ends. Moroccanoil's High Shine Gloss Mask is a shine mask that is aimed at color-treated hair. Pureology's Color Fanatic Top Coat plus Tone Gloss is the top coat for the days between masks. OUAI's Hair Gloss is an in-shower shine treatment, quick and fuss-free. L'Oréal Professionnel's Vitamino Color Spectrum is a color-protecting shine mask, which suits the weeks when you want the shade to hold. Kérastase's Gloss Absolu Glaze Drops are an anti-frizz hair oil, so a few drops go a long way.

What I would skip: hot tools at full heat and long, steamy showers in the first week after dyeing. Both push color out faster. Also skip sunbathing with wet, freshly colored hair when you can, and put on a hat or scarf for long days outside.

Apply masks to the lengths and ends only, and leave the roots alone. Rinse thoroughly, since leftover mask can make color-treated hair look flat by the next morning.

Here is the plan I would follow. Dye on the day you have nothing on, wait a few days before the first wash, then use a color-safe shampoo and cool water. Add a mask once a week and a gloss when hair starts to feel matte, and stay patient through the first few washes.

Keep an old pillowcase for the first few nights, because fresh color can rub off. When color starts to fade, refresh it at your own pace, and do a strand test first. If a shade has faded to something you love, leave it alone. Fading is sometimes the best part.

And if you want to change shades, mix two colors on a small strand before committing. It saves an unhappy afternoon. Take a photo in daylight after each wash, too, so you can see how quickly the color is really fading, and note which shampoo you used that day. If you want to keep browsing, I also put together L'Oréal Mascara and the Paris Chemist Who Started With Hair Dye and Orange Hair Dye, From Neon Semi Permanents to Copper Permanents.