1. Install build tools

sudo apt-get install devscripts dh-make

2. Prepare source code

mkdir -p ~/tmp/testdeb/debian && cd ~/tmp/testdeb
touch testhello.c Makefile
touch debian/{changelog,compat,control,rules}
echo 9 > debian/compat

testhello.c

#include <stdio.h>

int main (int argc, char *argv[])
{
    printf("Hello\n");

    return 0;
}

Makefile

OBJS = testhello.o

CC = gcc -g

all:$(OBJS)
    $(CC) -o testhello $(OBJS)

clean:
    rm -f *.o testhello

.PHONY:all clean

debian/changelog

testhello (1.0-1) unstable; urgency=medium

  * init

 -- xxx <[email protected]>  Mon, 26 Jun 2017 17:25:36 +0800

debian/control

Source: testhello
Priority: optional
Maintainer: xxx <[email protected]>
Build-Depends: debhelper (>=9)
Standards-Version: 3.9.6

Package: testhello
Architecture: any
Depends: ${shlibs:Depends}, ${misc:Depends}
Description: testhello

debian/rules

#!/usr/bin/make -f  
%:  
    dh $@

Final directory tree

./testhello.c
./debian
./debian/compat
./debian/changelog
./debian/control
./debian/rules
./Makefile

3. Build

debuild -us -uc -b

ref:

HOWTO: Build debian packages for simple shell scripts

HowToPackageForDebian