I'm going to provide some sources for this when I get off my phone and back to my desk.

Four of the accounts that we have concerning Pope Urban's preaching of the Crusade write as if they were present - these are scribes and scholars of the day. They would have brought word to their respects be courts and patrons. Fulcher of Chartres wrote the earliest account of the Council of Clermont and while we do not have a direct transcript of what Urban II said there, we can begin to piece it together from what he, Robert the Monk, Baldric of Dol and Guibert of Nogent wrote of it. The accounts would be repeated, garbled and spread through word of mouth.

Fulcher's account does not mention any Crusade for Jerusalem and some hypothesize that it was a secondary objective added after the gathering of the nobles for the first crusade. (Pope Urban II's Preaching of the First Crusade H.E.J. Cowdrey) This is significant (to me) because it is the earliest of the accounts that we have of the council.

Once the word reached your court, you have some decisions to make. The declaration that one was going on crusade was simply that - a declaration. The actual process was somewhat more difficult. Traditional pilgrims traveled to Jerusalem unarmed. (Early Crusaders and the Cost of Crusading- Jonathan Riley-Smith) The Council of Clermont specifies warriors for Christendom, and if you're a man of any means that will also require whatever additional men and material you can muster.

Going on crusade was an enormously expensive endeavor. As a minor noble your best bet is to hook up with a greater lord who is also going on crusade. There were several routes considered but the First Crusade took the land route which is a lot of hostile ground to cover. You're going to need to liquidate as many of your assets (land) that you can and call in any debts you are owed to get the capital you need for this adventure.