Poking means doing something risky. Trying something new. Poking comes with inventing, starting, doing. It's difficult to poke, because there is risk of failing. If you cannot fail, it's polishing. Because when it's not dangerous or risky, it's usually boring. The world now gives prizes to people willing to poke. People willing to ask difficult questions and willing to start. People willing to take the risk. Poking can be as complex as starting a new venture, but it could be as ordinary as facing a crucial conversation with your coworker, boss or partner.
Polishing means sustaining the status quo. Polishing comes in many forms. It might be sending endless text messages to a friend, Facebook chatting, twittering, starting a blog. Polishing usually doesn't have any real goals, no progress and no deadlines. These three signs are typical for polishing. Polishers don't start anything of value. Easier to stay in the crowd.
No matter how hard you polish, there will be little results (if any). Instead, poke. Try something new, face something difficult. If there is something to loose, then it's interesting.