I'd suggest first finding a standard existing workout thats already built, whether from muscle and fitness magazine, t-nation, Madcow, ripptoe, whatever, and just following it religiously for a while. You really need to change your workout structure every 6-12 weeks if you aren't doing DC style, or one of the others that has high variability built in.
And then diet, we probably need to work on particulars and details there too.
If either the OTC or other anabolics made it easy, or the gains were easy to keep post cycle, there would be a hell of a lot more ripped 250lb guys on this board than there are. The fact is that the steroids make short term non-maintained gains for most people because their fundamentals aren't as strong as they thought. And even with all that in place, adding a REAL inch to your arms is still a years worth of work even with juice (again, or there would be tons of guys running around with 24" arms
)