Identify your use case: shredding/topping, melting in sandwiches, or stirring into sauces/bakes.
Choose the closest melt match first: Monterey Jack/Colby Jack for melt + chew; Gruyère/provolone for deeper savory melt.
Apply the listed ratio: use 1:1 for most swaps; for mozzarella, start at ¾ the amount and adjust to taste.
If the substitute is milder than cheddar, boost flavor gradually (pinch of salt, small mustard powder pinch, or a tiny lemon squeeze).
Test melt behavior: add shredded cheese to hot food and stir briefly for sauce dishes; for baking, add on top near the end.