rename this file to `ks.cfg` and place within the root of the ISO. Then add `inst.ks=cdrom` to the boot options within `grub.cfg` and `isolinux.cfg`

CentOS-minimal.ks.cfg

#version=DEVEL

# Reference: https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Installation_Guide/sect-kickstart-syntax.html

# System authorization information
auth --enableshadow --passalgo=sha512
# Use CDROM installation media
install
cdrom
# Use text install
text
# Run the Setup Agent on first boot
firstboot --enable
ignoredisk --only-use=sda
# Keyboard layouts
keyboard --vckeymap=us --xlayouts='us'
# System language
lang en_US.UTF-8

# Network information
network  --bootproto=dhcp --device=eth0 --ipv6=auto --activate
#  https://www.centos.org/forums/viewtopic.php?t=11861
# http://serverfault.com/questions/441497/how-to-get-centos-6-kickstart-to-ask-for-hostname
#network --device=eth0 --bootproto=query
network --hostname=centostestks

#Root password
rootpw --lock
# System services
services --disabled="chronyd"
# System timezone
timezone America/Los_Angeles --isUtc --nontp
# password is password
user --groups=wheel --name=centos --password=$6$CcsLDN2EUviPeIeU$yrM8iKn8BDOvaZZvIJS/4PU4tfRh2/sVVpKU/ZlzX6HcWyZiV1GAteRfuEG869LBEHP4RhuN.qNZLiPaOPG2j. --iscrypted --gecos="centos"
# System bootloader configuration
bootloader --location=mbr --boot-drive=sda

# Partition clearing information
clearpart --none --initlabel

autopart --type=lvm

# agree to EULA
eula --agreed

# Attempt to eject the installation DVD (if installing from a DVD) before rebooting.
reboot --eject

%packages
@^minimal
@core
curl
%end

%addon com_redhat_kdump --disable

%end

# run after setup
%post

curl -o install_bigfix.sh https://raw.githubusercontent.com/jgstew/tools/master/bash/install_bigfix.sh
chmod u+x install_bigfix.sh
./install_bigfix.sh alpha.bigfix.com

%end

References:

• http://www.smorgasbork.com/2012/01/04/building-a-custom-centos-7-kickstart-disc-part-3/
• https://www.centos.org/docs/5/html/Installation_Guide-en-US/s1-kickstart2-putkickstarthere.html
• https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Installation_Guide/chap-anaconda-boot-options.html