You got it: simmer bones in weakly acidic water for hours, then strain out solids. You'll want to skim the foam that forms (affects the taste), and no need to salt.
I have not to this date found a standard amount of water to be used for stockmaking, other than "enough to cover everything". That usually ends up being a lot of water since bones don't stack very efficiently, so the next step after simmering for however long you're doing it (12-48 hours for poultry, usually) is to reduce the strained stock to about a pint per pound of bones. At that point you're about ready to use it in whatever you want: soups, reduced for sauce, added to shredded meat to add moisture and flavor, the list goes on.
You'll probably want to de-fat the stock. Why? Stock is an ingredient and there will be times you don't want to add fat along with for textural or taste reasons. Just chill the stock and separate the hardened fat, and store it in a separate container to use later. A basic stock isn't seasoned with salt, herbs, or spices for the same reasons, you want to maintain the versatility. You can always add them later, but you can't take them out once in -- this is especially important when you're e.g. reducing stock down to a sauce, all of a sudden the salt and spices just got concentrated more than 10x.
If you've got the time, go ahead and let it simmer for more than just 12 hours, the taste (and nutrition) will be better. Just keep topping the water up whenever it goes below the level of the bones.