The only way is saying:" Gracias mi buen amigo" You will NEVER translate "word by word" because you will Insult your friend calling him "Old". If you both are really close friends then you may say : Gracias mi "viejo amigo" but NEVER "Gracias mi "amigo viejo" because you would be saying that he / she is an "old person". Hope this helps!
To say hello friend in Spanish you can say "hola amigo".
my friend = mi amigo
amigo
Amigo is one way of saying friend in Spanish. Amiga is for a girl.
"Para mi amigo/a" = For my friend
You can say "¿Cómo estás, amigo?"
para amigo(a) = for friend (male/female)
a mi amigo
el amigo/a
mi amigo
Amiga
"All about my friend" is "Todo sobre mi amigo (amiga if feminine)" in Spanish.