When not part of a conversation, obsessively chew on my lips. This produces a kind of tic effect that should indicate that there is a disorder.
I don't think that tics are strongly associated with schizophrenia.
In any case, you've done some reading on symptoms of schizophrenia, so pardon me if you already know what I'm telling you. Schizophrenia symptoms are divided into positive symptoms (psychosis, delusions, hallucinations, disordered thoughts) and negative symptoms (blunted affect, alogia, anhedonia, diminished movement). Medications used to treat schizophrenia are commonly much more effective at managing the positive symptoms than the negative symptoms. Hence, if Danny is effectively managed, he would probably not be floridly psychotic unless he stops taking his medications.
So if you wanted to portray managed schizophrenia in a non-outrageous way, I think that you should try to exhibit some of the negative symptoms. Since it's hard to get a good handle on what blunted affect or alogia or diminished movement really are, you would benefit from talking to and observing real people with schizophrenia.
While on my psychiatry rotation, I interacted with a handful of schizophrenic patients, and the best way that I can describe them is that they always appear to be uninterested in what you're doing or saying. You can tell a joke and they won't smile; you can show concern and they won't acknowledge it; you can press for detail but they usually won't say more than a few words.