Resources

https://wiki.debian.org/BuildingTutorial#Introduction

Requirements

# apt-get install build-essential fakeroot devscripts

Configure apt

# vim /etc/apt/sources.list
add:
deb-src http://httpredir.debian.org/debian unstable main
then:
# apt-get update

Create a working directory

$ mkdir -p src/debian/; cd src/debian
$ cd src/debian/
$ apt-get source <package>
$ cd <package_dir>

follow build instructions in README file

Get the build dependencies

# apt-get build-dep <package>