Centos Sftp Ssh - How always create files with rwx-rwx-r-x and always owned by a certain group

I have a user myuser, which is only allowed to coect to ssh via sftp. I'd like this user to always create files with rwx-rwx-r-x and always owned by the group apache. I've tried to accomplish the file permissions part with umask, but in umask files and directories get different permissions for the same umask. Help is appreciated.