this will add a new command line (subl) commend to open files with sublime text within git bash.
First, you need to create .bash_profile under /users/username directory.
you can check your home folder by typing echo ~ in your git bash.
this will set the PATH and other environmental variables for the shell.
and then edit with sublime or notepad the .bash_profile file and add the below command
you can use your git bash and type the below command to create the modified .bash_profile in your home directory.
This will only work if you are logged in via console. if you want the add the alias for every users, you can create .bashrc file instead
you can download .modified .bashsrc and .bash_profile and paste it on your home folder as well(/users/username)
http://www.joshstaiger.org/archives/2005/07/bash_profile_vs.html
the link above explains the difference between bash_profile and bashrc