What about Candy's manner suggests that he avoids causing anyone displeasure? How does his name reflect his character?
Many things about Candy's manner suggest that he tries to avoid displeasure. The first comes when he enters. Before he enters, he listens to hear George and Lenny being briefed. When he's accuses of listening, he denies it. When he tells what he was doing, he claims to have been doing his job (something no one could fault him for).
In general, he is quiet and moves slowly, as if trying not to startle anyone. He asks George not to repeat what he's said, so as not to draw attention/offend anyone. He is reassured when George says something unpleasant about someone else.
Of course, the biggest thing is that he lets the others kill his dog, who he loves, to give in to their desires (and not give offense).
His name only moderate reflects this. He tries to be sweet, but to be honest, he doesn't always succeed.