How to create a directory and give permission in single command

When the directory already exist:

mkdir -m 777 /path/to/your/dir

When the directory does not exist and you want to create the parent directories:

mkdir -m 777 -p /parent/dirs/to/create/your/dir

According to mkdir's man page...

mkdir -m 777 dirname

install -d -m 0777 /your/dir

should give you what you want. Be aware that every user has the right to write add and delete files in that directory.