As you’re the new postman, you need to learn how to read.
Walk to the right to leave the post office and in the street walk all the way to the left into the alley. Talk to the bum who is, surprise, surprise, Mrs. Lumpycakes, English teacher. Ask for English lessons and you can get lessons but you need to be enrolled first. All you need is some form of identification along the lines of a photograph.
Walk to the right to leave the alley and since there’s only one person with a camera, walk all the way to the right and enter the apartment building. Use door #33 to enter Mika’s apartment and ask her to take a PHOTOGRAPH of you.
Leave the apartment and walk south again to leave the building. Walk all the way to the left to return to the bum in the alley. Give the photograph to him and he’ll teach you how to read. Now you can do your job.
Look at the first letter in your inventory, the one with the red stamp. It’s addressed to Mrs. Lumpycakes. Give the letter to the bum. There’s another letter, the brown one, for Vicks at the hospital. Walk to the right to leave the alley and walk north to the right of Dominatrix.
Walk into the hospital and give the brown envelope to Vicks. Walk south twice to return to the main street and walk all the way to the right, past the apartment block to the cemetery. From there to the right to reach the gym. Give the last letter to Mr. Namyah. Since that was the last one, you’ll return to the post office.
On the corner of the table is a green envelope that wasn’t there before. Take the ENVELOPE and look at the envelope in your inventory. It’s for Dr. Die Vie Es. You wonder what it says. Fortunately there’s also a steamer in the room so use the envelope on the steamer to open it.
The message in the letter doesn’t sound very good and it’s best to warn someone as quick as possible. Walk to the right to leave the post office and in the street walk to the left to reach Scid’s. Go inside and find the election party in full swing. Give the letter to the mayor on the far left and he’ll read it. But you’re completely misunderstood and end up in jail.
After the conversation with No-Beard, you need to get out of jail. Use your hand (hook) on the lock to open the cell and you’ll follow No-Beard to the lost treasure. Standing behind him, use your hand to give him a push.
Game source: A copy of the game was found here on the internet.