Three Kingdoms: I'm Lü Bu, and I Grow Stronger by Farming Overseas

After transmigrating and becoming Lü Bu, I decided to do things differently this time. During the Three Kingdoms era, Cao Wei grew stronger by hunting down the nomadic tribes, Shu Han by hunting down the southern tribes, and Sun Wu by hunting down the Shanyue. So surely it makes sense for me, Lü Fengxian, to grow stronger by hunting overseas? But to hunt overseas, I first need territory of my own, and it has to be near the sea. Then I need a large ship capable of long voyages, or I won't be able to get anywhere. Then I need someone skilled in naval warfare, or I'll just be left staring at my ship. Most importantly, I have to remain strong enough that no one dares to mess with me. Ideally, I should weaken the people around me, too. But Lü Bu has just been soundly defeated by Cao Cao in Yan Province and is now on the verge of fleeing at any moment...