1. A good question. Have you tried figuring out the answer yourself?
2. Have you been in the Beast's Outer Lair?
3. Have you ever tried saying your name as the Beast demands?
4. There are at least a dozen ways to say your name: SAY MY NAME or SAY "ARTHUR DENT" or SAY "MY NAME IS ARTHUR DENT" or SAY "I AM ARTHUR DENT" or TELL THE BEAST MY NAME or TELL MY NAME TO THE BEAST. You could also say BEAST, MY NAME IS ARTHUR DENT or BEAST, I'M ARTHUR DENT. There are some others but you've probably got the general idea by now.
