Bridal Portraits

I take my bridal portraits tomorrow!  I was supposed to take them today, but it was cold and drizzly.  The sun is supposed to come out at 10 tomorrow and it'll be in the 60s .  Hooman and I are shooting at Duke Gardens, so I'm going to bring a sheet to put underneath in case the ground is wet.  Between our schedules and the weather, we had no other options.  I even saw some flurries on the weather schedule for next week!  I'm not sure what size to order my photo or whether I want canvas or print, any suggestions?