Make the pretzels in advance and bake them until just before they start to brown. Pull out and let cool - freeze if more than a day in advance. Finish the baking as the guests arrive. There are so much better fresh out of the oven. Otherwise you will be busy making pretzels while everyone else is drinking, eating and socializing. Unless of course you have a giant kitchen and with room for everyone.
Of course not that I ever do this. We have several large food and beer oriented parties a year and I'm invariably still in the kitchen 2 hrs after the guests have been arriving.