Get the Whitepaper called Teaching an Old Dog (not that new) Tricks – Stego in TCP/IP made easy (part-1).
You can download it from the following link: https://packetstormsecurity.com/files/download/140072/teaching-an-old-dog.pdf
Source: https://packetstormsecurity.com/files/140072/Teaching-An-Old-Dog-Not-That-New-Tricks-Stego-In-TCP-IP-Made-Easy-Part-1.html