When to prepare the nursery

I recently got the call - we are doing our home study and training for older child adoption this September. This means that i could be a mom by December. Same time my sister is Due to have her first baby. I don't if that is why she recently discouraged me from registering for stuff i MIGHT NEED until AFTER the placement. I was stunned. When does she think i will have time. I asked my Sister in Law - she said the same thing. Then I asked my best friend. She felt the same way. wait until closer to placement. I said forget it and I am going tomorrow to register at Sears for the things I may want or need, with my Mom, who up until now has been giving me the most grief about adopting an older child.