When I had a corporate job, I would place my commodity options orders near the end of the regular trading sessions, which overlapped with the time I was "out to lunch."
It helped that I had a private office and usually ate at my desk anyway, but I was very conscious to not spend more than about 15 minutes glancing at news, quotes or placing orders.
You don't want to find yourself in a situation where someone could make a case that you're stealing company time* and you don't want to trade in such size that you're worried about positions and regularly checking on them via company computers or your own phone during the work day.
*a tricky issue for companies and managers because most people waste at least some time each day with online sports sites, newspapers, social media, or shopping or yapping with their wife, kids and friends on the phone.