Blooming is just a fancy way to say cooling them at room temperature.
Generally after a hot water bath, you will "shower" or dip them with cold water to bring the temp down to around 110* or less. The reason for this is to prevent shrinkage. Then hang them to "bloom" at room temperature for about 3 hours. Sausage will darken back up during the blooming process. My school of thought is to then hold them in the fridge at least overnight or a little longer as everything seems to taste better the next day! Actually I'm sure there is some technical reason for the flavors tending to meld with time.
PS - you only want to do this with meat that has cure in it. Un-cured meat will be outside the danger temperature zone for too long. If you are making sausages without cure, then it's a "fresh" sausage and should be refrigerated until cooking and then served immediately. The reason I add this is I have seen recipes for Kielbasa that do and do not have cure.
I see Shannon127's recipe does use cure#1 so you are fine.