A friend needs new boots. You like the design. Before that turns into a loot argument, check whether you both need to win anything at all.
Three cases worth knowing
Blizzard’s deep-dive recap describes these appearance rules:
Bind-on-pickup Uncommon or Rare dungeon items: all eligible looters get the appearance when the item is looted.
Epic raid drops: the appearance goes only to the player the item binds to.
Poor or Common items: looting unlocks the appearance without first requiring the item to bind.
Ask before the roll
“Is it an upgrade, or are you after the look?” is a useful question. It leaves room for someone to explain what they need without turning the whole run into a debate.
For those boots, check the quality, binding and where they dropped. The dungeon rule above is specific. It does not say every nearby player gets every appearance, and “eligible looters” is not defined further in that passage.
If your case falls outside those categories, agree what to do with the group. This guide is not a reason to override the loot agreement.
Collecting it does not mean you can wear it
You still collect appearances with transmog switched off. Applying them follows item-type rules: cloth goes onto cloth, plate onto plate. Low-level characters also face appearance-level restrictions; Blizzard says those lift at level 60 for valid collected appearances.
Decide who needs the item before a cosmetic becomes a disagreement. A quick question is cheaper than a ruined evening.