This video from FoodWishes.com demonstrates how to make garlic Parmesan croutons. This is a great recipe for homemade croutons which will be much better than the ones you can buy at a store.
He first mixes olive oil and finely mixed garlic and lets it infuse for a few hours at room temperature. He cuts a loaf of day-old French bread into cubes, and tosses the bread cubes with the garlic oil. He then adds grated Parmesan cheese and freshly ground black pepper, and a little salt and cayenne or paprika, and a pinch of dry Italian herbs.
He spreads the croutons in a single layer on a pan and puts it into a 300 degree oven for 15 minutes. Toss them and bake them another 15 minutes. Push them together with a spatula, sprinkle more Parmesan cheese, and bake them for another 10-20 minutes until they're done. Let them cool completely before packaging them for storage.