What was the seed of evolution composed of, and how was it planted?

Research the field of abiogenesis.

The prevailing consensus is that nondeterministic self-replicating carbon molecules were created as a result of electrical discharges surging through primordial oceans of organic compounds.

The Big Bang explains how the universe developed from its initial state to the way it exists today. It has really nothing to do with abiogenesis or evolution.

The seed of evolution was a thought in the mind of Darwin and was planted there by Satan. God created everything using his first creation, his Son. We can barely understand the world around us and our universe, although we are still learning. How in the world can we even begin to understand God and that God always existed, he has no beginning and no end, God is eternal. This is too much for our meager minds to comprehend, and just because we cannot understand this is no reason just to dismiss God as not existing. If the Big Bang started from something that you claim obviously just existed without a beginning, how can you expect us to believe that when you claim God could not exist without a beginning?

For the first billion years or so, there was anaerobic slime - red slime.

Then Green Slime emerged and produced oxygen which destroyed 99.9% of the red slime. (Red Tides are colonies of anaerobic slime).

Then there is an odd theory that plants evolved out of the green slime while animals evolved out of the red slime. The problem with this model is that oxygen is NOT poisonous to us gods-like creatures it was early red slime.

"Elohim" is a plural noun. Combining that fact with Gen. 1:26 where Elohim says, "Let us make man in our own image"

http://www.rightwordtruth.com/elohim.htm

PAPER 58 - LIFE ESTABLISHMENT ON URANTIA - P.664

P.664 - §2 600,000,000 years ago the commission of Life Carriers sent out from Jerusem arrived on Urantia and began the study of physical conditions preparatory to launching life on world number 606 of the Satania system. This was to be our six hundred and sixth experience with the initiation of the Nebadon life patterns in Satania and our sixtieth opportunity to make changes and institute modifications in the basic and standard life designs of the local universe.

the God Yahweh crash landed in the deserts sands of the Dead Sea emerging from the craft with the seed of life in a canister.

Abiogenesis is the best idea scientists have now, and it seems to be pretty solid.

As for all matter, it didn't "get there" it already was "there".