That depends whether you know how to program at all.  If not, then choose a language and study it.. but I'll assume you do know how.  In which case, just search for tutorials on the net, there is no reason this side of the 9th #### that you need to spend $60 on a book from Amazon, everything is fairly simple and well-tutorialized.  you'll need a solid grasp of socket programming and a good grasp of the telnet protocol would be useful but neither require a master's in comp prog :p