The step after sensing mana was a tad more difficult since he now had to start building the foundation that would prop him up as a god of the sea. Different from becoming aware of mana, a factual building block of nature that existed just as much as he or any other particle did, somehow taking that mana and building a sea of it within himself was a little less clear-cut.
Ackster wasn't sure if it was actually helpful, but he had adored fantasy stories in his past life. He probably still did to some degree, though living one had taken some charm off it. He also didn't have time to read stories at the moment. But he felt that he had a certain edge, thanks to his knowledge of different fictional worlds and power systems that could help him shape a mental image.
Most of it was a little fuzzy, but Ackster still had his imagination, so it didn't take long before he could start with the first drop of water that would become his Sea.