You probably would like to look into setting the "PS1" environment variable.
this is ususally done in a file in your home directory called .bashrc (or, sometimes, .bash_profile)
and do a search (press the / key) for PS1, or do a google search on how to change the variable. Essentially, it is a string (with variables such as \h which translates to hostname) that is displayed as your prompt.
PS1="[\u@\h \w]\\$ "
would give you something like
So play around with it till you have it as you'd like.