start at the beginning and work your way through it.
it worked with your old plug, right? first step would be to put that back in and try it.
then the plug wire. if that doesn't work, check and/or re-do all your electrical connections.
if it still doesn't work, then it could be your CDI.
basically, you eliminate one thing at a time. it worked before, so put it back to the way it worked. if it doesn't work, then go down the line to the next component.
too many times people just give up and replace everything, when only one thing is messed up. i don't know how many times i read "my bike won't run, i'm buying a new magneto." for some reason, we never seem to hear back from these people.
also, when you take your time and actually diagnose the problem, you're learning. if it happens again, you might be able to do a roadside repair in 5 minutes, 'cause you learned what to look for, and you ain't pushing your bike home.