One need to have gcc installed for that you need to install xcode along with command line tools. To install the same one can refer to this link for xcode 5.0.1. Libevent is required to be installed for memcached, if it is already
installed on your machine you can skip this step.
Create temp directory and change directory to that location and execute following commands.
$ curl -O http://www.monkey.org/~provos/libevent-1.4.14-stable.tar.gz
$ tar xzvf libevent-1.4.14-stable.tar.gz
$ cd libevent-1.4.14-stable
$ ./configure
$ make
$ sudo make install
now install memcached
$ curl -O http://memcached.googlecode.com/files/memcached-1.4.15.tar.gz
$ tar -zxvf memcached-1.4.15.tar.gz
$ cd memcached-1.4.15
$ ./configure
$ make
$ sudo make install
Above steps will install the memcached on your OS-X. Once it is done you can start it.
$ memcached -d -p 11211