Postgresql – Can’t connect to local Postgres databases

After trying to install Postgres using Postgres.app and EnterpriseDB, I decided to re-install it using Homebrew (As I got some problems connecting to database).

PYTHON=/usr/local/bin/python brew install postgresql
initdb -A trust /usr/local/var/postgres
initdb /usr/local/var/postgres -E utf8


mkdir -p ~/Library/LaunchAgents
cp /usr/local/Cellar/postgresql/9.3.2/homebrew.mxcl.postgresql.plist ~/Library/LaunchAgents/
launchctl load -w ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist

I am working to create a database using Postgres.
Whenever I try to create database using command line, I got this problem :

MACBOOK:~ macbook$ postgres -D /usr/local/var/postgres

LOG: could not bind IPv6 socket: Address already in use HINT: Is
another postmaster already running on port 5432? If not, wait a few
seconds and retry. LOG: could not bind IPv4 socket: Address already
in use HINT: Is another postmaster already running on port 5432? If
not, wait a few seconds and retry. LOG: could not bind IPv6 socket:
Address already in use HINT: Is another postmaster already running on
port 5432? If not, wait a few seconds and retry. WARNING: could not
create listen socket for "localhost" FATAL: could not create any
TCP/IP sockets

Or I face this problem

Is the server running locally and accepting connections on Unix
domain socket "/var/pgsql_socket/.s.PGSQL.5432"?

Any ideas to solve this problem?