As stated on Wikipedia (not always my go-to source, as a former writing teacher and aspiring English Literature scholar):
"The phrase 'What would Jesus do?' (often abbreviated to WWJD) became popular, particularly in the United States but elsewhere as well, in the 1990s and as a personal motto for adherents of Christianity who used the phrase as a reminder of their belief in a moral imperative to act in a manner that would demonstrate the love of Jesus through the actions of the adherents."
So how does Jesus show his love in this passage, and how should we also act in the matter that "demonstrate[s] the love of Jesus through . . . actions"?
At the beginning of this passage, Jesus shows his concern for his disciples. In verse 31 Jesus says to them: "'Come away to a deserted place all by yourselves and rest a while.’ For many were coming and going, and they had no leisure even to eat". In the midst of busy-ness and demands, Jesus' concern for those with him in the midst of this frenzy--those whom he had sent out to spread the message and heal others--is that they get some rest, that they have balance in their lives. We all know that we can only go at a breakneck pace for a certain amount of time before we have to refuel--our capacities are not unlimited. We get tired; we need recovery time. What does Jesus do? He cares that they get this time of respite. And so they get in a boar and set out to do just that.
Soon, however, they encounter more people--described thusly, in verses 33-34: "Now many saw them going and recognized them, and they hurried there on foot from all the towns and arrived ahead of them. As he went ashore, he saw a great crowd . . .". And what does Jesus do? This: "[H]e had compassion for them, because they were like sheep without a shepherd; and he began to teach them many things". Because of their need, Jesus himself changed what he was going to do.
It is important even for Jesus to get some time off--the Gospels tell us frequently of him going off by himself to a quiet remote place, just as he and his disciples set out to do here. And he would be certain to prioritize doing that once this time of the crowd's need had been met. But this context demanded that he not rigidly stick with a particular plan when the situation demanded that he do something else. In both situations addressed here--the escaping with the disciples because of their need for rest, and the responding to the crowd because of their need for his guidance, teaching and inspiration--Jesus was motivated by concern for others.
Guidance for you and me as we ask "What would Jesus do?" as a guide for what we should do. Do what demonstrates concern for others. What that looks like depends on what happens. And then what else happens.
GOSPEL Mark 6:30-34, 53-56
30 The apostles gathered around Jesus, and told him all that they had done and taught. 31 He said to them, ‘Come away to a deserted place all by yourselves and rest a while.’ For many were coming and going, and they had no leisure even to eat. 32 And they went away in the boat to a deserted place by themselves. 33 Now many saw them going and recognized them, and they hurried there on foot from all the towns and arrived ahead of them. 34 As he went ashore, he saw a great crowd; and he had compassion for them, because they were like sheep without a shepherd; and he began to teach them many things.
53 When they had crossed over, they came to land at Gennesaret and moored the boat. 54 When they got out of the boat, people at once recognized him, 55 and rushed about that whole region and began to bring the sick on mats to wherever they heard he was. 56 And wherever he went, into villages or cities or farms, they laid the sick in the market-places, and begged him that they might touch even the fringe of his cloak; and all who touched it were healed.