There are generally five elements to stuffing:
Starch. You can use any sort of bread, as well as rice or even potatoes.
Herbs. Use fresh or dried herbs, such as classic sage. Or flavour with thyme, rosemary or a combination.
Seasonings. Season to taste using salt, pepper, garlic — or all three.
Vegetables, fruits and nuts: Add savoury and sweet notes by including veg such as onions and celery, fresh or dried fruits (like apples, sultanas or currants) and nuts such as walnuts or pecans.
Meat or seafood. Stuffing recipes can include meat (like sausagemeat and bacon) or seafood, including oysters, crab and prawns.
Liquid. Use chicken or vegetable stock to moisten the stuffing. Or, add bright flavours with orange juice or wine.