If you go to
http://www.apa-abayouthpoultryclub.org/educational_material.htm , there are a number of links to articles and information on showmanship.
Being enthusiastic and telling MORE than is asked is good (for example, if asked to show the wing, properly show it and tell the judge the parts of the wing, why one would look at the wing, any interesting trivia (such as some birds having a claw on the wing), and otherwise responding THOROUGHLY to the judges request, not just MEETING it.
Know the faults and good points of your specific bird--for example, tell the judge that you think it has awesome type, but the toes are not quite what you would perfer--and what you think it should be. Tell what you like about your specific bird and why. Showmanship is SALESMANSHIP. Talk directly to the judge, not any audience. Be honest and say that you don't know if you don't.
Work with your bird ahead of time so that it easily accepts handling. Try to know more than is asked for your level.