Your main ingredient is salt and how much depends on your taste.
Start with 3/4 tsp morton's kosher salt per pound (1 part) add an equal amount of coarse black pepper. 1/2 part paprika. Then add granulated garlic and cumin to taste.
I also add about 1/16 part Msg. It is easier to reproduce if your final measurements are by grams. (You can back into the salt and pepper measurements).