Be bolshi - if you are trying to get in contact with someone important and hitting a blank wall keep going, don’t just give up at their secretary. If you are ringing a company to speak to someone senior always meake sure you know their name, not just their job title. If you are setting up in business on your own try to gather people around you who can help you, don’t try to do everything yourself. You’ll be surprised at the skills and expertise that your own circle of friends, family and aquaintances can provide you with, and usually for free.