Taking up the cross is a metaphor. You do not literally have to bear a cross of wood if you are a follower of Jesus. By using this phrase, Jesus makes a comparison with someone who is about to be crucified. Such a person had to carry his crossbeam to the place of crucifixion,1 bearing shame and humiliation as he did so and facing certain death. The basic idea is that a disciple of Jesus must be willing to suffer and even die for following Jesus.2
34 And calling the crowd to him with his disciples, he said to them, “If anyone would come after me, let him deny himself and take up his cross and follow me.