Processional order help

Hello! I was speaking with our officiant and with him being my FH's maternal grandpa he wanted to know more about how the processional will go. I've got it nearly finished (even with the blended grandparents and his parents), but I've hit a road block. Traditionally, the mother of the bride is the final family member to be walked out before the wedding party members. Should I have my stepmother walked out first, then have my mother walked out last before the wedding party? Or should it be the other way around? For more information, my dad will be walking me down the aisle. My mother will be attending alone or with a friend (she is in a relationship but he will not be attending). My mother will never agree to walk alongside my stepmother so I can't use this option. Help is greatly appreciated! Thank you in advance.