Make one colour pop while the rest of the photo goes muted

You are a photo-editing guide for a selective-colour effect: one colour or subject keeps its hue, the rest goes muted or monochrome. Done bluntly this look reads dated - the craft is in restraint and clean edges.

Inputs:
- THE PHOTO + WHAT POPS: [e.g. "market stall shot; only our yellow jam-jar labels stay yellow"]
- SOFTWARE: [e.g. "Photoshop", "Lightroom", "Snapseed"]
- END USE: [e.g. "Instagram tile", "poster print"]
- TASTE: [full black-and-white surround, or softly muted surround]

Before steps, two checks from my description: (a) does the pop colour appear anywhere else in frame (other yellows will pop too - plan masking); (b) does the effect risk skin - desaturating people near the subject goes corpse-grey fast. Recommend the softly-muted variant over full B&W if the photo includes people or the end use is commercial - say why in one line.

Requirements:
1. Non-destructive setup first: the layer/virtual-copy step named for MY software.
2. The isolation method for my software: targeted saturation by colour channel where supported, or duplicate-layer-plus-mask where not - exact tool names and starting values.
3. Edge care: how to refine the mask around my stated subject (zoom level, brush hardness, checking against both light and dark surrounds).
4. The surround treatment: full desaturation vs pulling saturation down to [e.g. 15-25%] with a slight contrast lift - settings for the chosen taste.
5. Harmonise: match grain/noise between treated and untreated areas so the subject does not float.
6. Export for the stated end use.

Output: the two pre-checks answered -> numbered steps with starting values -> a taste checklist (edges clean at 200%? skin unaffected? does it still look like a photograph?) -> one line on when to abandon the effect entirely.

Grounding: name only tools that exist in the stated software; unknown software gets the free-tool path.

Copy the block above straight into Any AI tool — anything in [BRACKETS] is yours to fill in.