DirectAdmin is a proprietary web-based control panel that you can install on your server which offers a variety of system-administration features. Lets Start the Panel installation:
Step 1: Logged in under the root user and that you have purchased the Direct Admin License from official site: https://www.directadmin.com/

Step 2: You need to update your server with latest packages so run the below command to update
# yum update

Next, we are going to install the packages that DirectAdmin needs on CentOS 6 to run properly. You can do that by executing the following command:
# yum install wget gcc gcc-c++ flex bison make bind bind-libs bind-utils openssl openssl-devel perl quota libaio libcom_err-devel libcurl-devel gd zlib-devel zip unzip libcap-devel cronie bzip2 cyrus-sasl-devel perl-ExtUtils-Embed autoconf automake libtool which patch mailx db4-devel

Step 3: Download the setup file to install the panel
# wget http://www.directadmin.com/setup.sh

Next, change the permission on the setup.sh file
# chmod 755 setup.sh

Run the script,
# ./setup.sh

You will be prompted for a client ID number, license ID number, and hostname. fill the required information to complete the installation. You can access DirectAdmin once its finished installing with your web-browser by navigating to http://your_server_ip:2222.

I hope this article will helps you!!
Done!