Quite frankly, I can't see how formula is good for an infant, period. Besides which the taste is terrible.
I did make my own formula for a couple of my children when they weaned before a year old. Basically it was a can of evaporated milk with a can of water, a "little" sugar ( not corn syrup or honey for babies under a year old) and a vitamin and mineral supplement added.
As long as your baby isn't sensitive to milk, this should work fine. If on the off chance she or he is, you can try to use evaporated goat's milk instead, but it is more expensive.
I used evaporated milk becuase it is broken down a bit more and easier to digest. And sorry to break it to other moms out there, standard formula IS based on cow's milk. If a kid can't handle those, that's when the soy and other disgusting substitutes come into play.
And, it was good enough for my parent's generation.
But, breast is most definitely best.