chmod.sh

for folder in $(find fileadmin typo3conf typo3temp uploads -type d); do chmod 2770 $folder; done;
for file in $(find fileadmin typo3conf typo3temp uploads -type f); do chmod 0660 $file; done;

# As Markus Blaschke pointed out there is a way better solution to this. Thanks!
# https://twitter.com/MarkusBlaschke
find fileadmin -type d -print0 | xargs -0 chmod 2770
find fileadmin -type f -print0 | xargs -0 chmod 0660

Ich usually use:

find fileadmin -type d -exec chmod 2770 {} +
find fileadmin -type f -exec chmod 0660 {} +

or, even more universal, but slower:

find fileadmin -type d -exec chmod 2770 {} ;
find fileadmin -type f -exec chmod 0660 {} ;

See some details about pros and cons: http://en.wikipedia.org/wiki/Xargs