YOU SAID:

I'm a big old guy covered with hair

INTO JAPANESE

私は毛で覆われて大きな古い男

BACK INTO ENGLISH

I was covered with hair bigger older man

INTO JAPANESE

私は髪に大きな古い男で覆われていた

BACK INTO ENGLISH

My hair was covered in a large old man

INTO JAPANESE

私の髪は、大きな古い男で覆われていた

BACK INTO ENGLISH

My hair was covered in a large old man