A "supergod" is needed to design the original god.
It's quite simple really - you simply axiomitise God. Just after I became a Christian at age 14, my brother challanged me with the age-old - if God made everything, who made God? The answer was obvious to me - God is by definition that ultimate being who is eternal and is not created. If he were created, he wouldn't be God, now would he? Worked a charm on my brother and on just about everyone since
Wouldn't try it here though, as there's some smart loigical types about!
I think your OP hits on a far more interesting point that I see repeatedly here - every man-made object has intelligence behind its design and construction (for loose definitions of intelligence). Life, which is far more complex than any man-made design, must therefore have SUPER-intelligence behind its design. It's the most bogus "logical" argument ever made.