How a skin is won
Each hole is worth one skin. The player with the lowest score on the hole — and no one else on that score — wins it. If two or more players share the lowest score, nobody wins the hole.
Carryovers
A tied hole's skin carries to the next hole, so the next outright winner takes two (or more). A run of halved holes is what makes skins exciting: by the back nine a single hole can be worth several.
What happens at the end
Decide in advance what to do with skins still carried after the last hole: play extra holes, split them, or simply leave them unclaimed. Leaving them is the simplest and needs no extra golf.
Gross or net
Net skins apply handicap strokes hole by hole, so a higher handicap can win a hole where they get a shot. Gross skins tend to go to the best player, which is fine when the group is close in ability.
Keep it friendly
Skins are often played for money, but they don't have to be. Counting skins as points makes it a format rather than a bet — and that's how TourCard keeps it: the winner is whoever holds the most skins.