Practice "ha, hi, fu..." over and over again until others can understand them clearly.
Example of failure (one letter off)
I joined the Ginrei-Kai and was attending an esophageal speech class at a time I felt considerably confident in my esophageal speech.
I was invited by some friends to visit an Izu spa. We got together and had a wonderful night for the first time in many years. We were on our way home.
At one of the souvenir stands, I said to a clerk, "Please give me a pack of hamaguri (clams)." The clerk said "Sure" and then proceeded to wrap me a package of amaguri (sweetened chestnuts). I hastily tried to protest, repeating my request. She looked puzzled and replied, "This is amaguri, sir." I was so ashamed and embarrassed, I settled for the amaguri and went home."
Being just one single letter off can be a real pain.
