Ok, best I can remember, my dad's mom came in with an escort (grandfather deceased). My mom's mom came in with an escort (grandfather followed behind). DMiL came in with 2 escorts (2 sons, best men) with DFiL following behind. My mom came in with an escort. DH, best men, and officiant came in from the back. I'm not sure how the other 2 got in, but I know they did my aisle runner at some point. Junior groomsman came in at some point, too. Then 3 bridesmaids came in, each alone. Flowergirls and ringbearer. MOH. Dad and me.
I hope I didn't forget anybody there! Here, if it's not a Catholic ceremony, the bridesmaids don't walk in with the groomsmen, but it's not something that would make anyone raise an eyebrow. It's just not common.