Gather all ingredients and equipment to ensure a smooth preparation.

Measure each spice accurately using measuring spoons and cups.

Combine the brown sugar, paprika, black pepper, salt, chili powder, garlic powder, onion powder, and cayenne pepper in a mixing bowl.

Whisk or stir thoroughly until the ingredients are evenly blended.

Taste a small pinch and adjust sweetness or heat by adding more sugar or cayenne if desired.

Transfer the rub to an airtight container for storage.

Let the rub rest for at least 30 minutes at room temperature to allow flavors to meld.

Generously apply the rub onto pork shoulder, pressing it into the meat to ensure even coverage.