Luke 5:3

‘And he entered into one of the boats, which was Simon's, and asked him to put out a little from the land. And he sat down and taught the multitudes out of the boat.'

So He boldly walked over and boarded Simon Peter's boat, and called to him and asked him to launch the boat a little away from the land so that He could preach from it. He would have known that it was a bit of an imposition on these hardworking men, but He was testing them out. Had they refused, or even shown reluctance, He might simply have passed them by. If they were to follow Him they would need guts. Then when Simon Peter had proved himself and had done what He asked, He sat down in the boat and taught the crowds from it.