Basic goal of the deck is getting your field spell out and summon kairyu-shin, either through jellyfish or by normal summoning it, then search sea stealth attack with kairyu-shin. Next turn immediately flip sea stealth in the draw phase, this can protect your monsters as well as your backrow.
There is also a cool combo if you open with jellyfish/umi, kairyu-shin and dark reef/sea stealth:
Summon kairyu-shin through jellyfish/umi>search sea stealth/dark reef (whichever you don't have)>set both>end phase>
Next turn activate dark reef>send umi to grave to special umi monsters>activate sea stealth>activate umi again>gl hf opponent :)