Even on OSX you should not be working with an admin account. Here are the steps to make homebrew usable for non admin users.
I assume brew has already been installed by an administrator and it's login is admin. Change admin below to the name of your admin account.
Under System Preferences create a new group "brew" and add your user to it. Then open the terminal and:
su - admin sudo chgrp -R brew /usr/local sudo chgrp -R brew /Library/Caches/Homebrew sudo chmod -R g+w /usr/local sudo chmod -R g+w /Library/Caches/Homebrew # and if you plan to use caskroom too: sudo mkdir -p /opt/homebrew-cask/Caskroom sudo chgrp -R brew /opt/homebrew-cask sudo chmod -R g+w /opt/homebrew-cask
(this logs in as the admin user and allows the members of the "brew" group to write to /usr/local and the Caches directory)
With your user account you can now run
brew doctor to check if everything is working as it should.
Credits: Visit this for some more detailed instructions.