Hi D:
I have a six-year old too (two of them in fact, boy & girl twins).
It's a special day for your daughter and you!
It's mixed bag of emotions for both of you, isn't it?!
Losing the first baby teeth can be scary and a little bloody for her, and not just a milestone, but a sweet & sad wonder for you about how the time flew by that such a sweet adorable baby turned into a little child who lost the first baby tooth.
When my child is not looking, I write a card (even a handmade one is fine and may even be preferable) with a wonderful message from the tooth fairy. I place a small amount of money (or other small thoughtful gift that you may want to give your child) and place it under the pillow after the child falls asleep. When my child wakes up, I ask her/him to check the pillow in the morning. She/he gets so excited in reading through the card and getting the gift. I encourage my children to share their gift with the other child who did not lose a tooth the night before. They agree to do so very sweetly and it leads to sweet hugs all around . Such a wonderful way to wake up in the morning. I definitely videotape and take pictures of their reaction in the morning (especially for their first tooth).
If they don't have a sibling to share their gift with, you can encourage them to share with a charity of your choice, with the church, etc.
I encourage my child to write a letter to the tooth fairy too (you can help them express their fears about tooth loss, their wonder and amazement, their experience with the tooth loss, what's it like to be a fairy, why do fairies collect teeth, etc.). You will be surprised by the dear things that they write to the Tooth Fairy. It will be another treasured momento for you to keep.
Here's some more advice about what to do immediately after the tooth loss that may help you might find helpful:
1) I first give the child a reassuring hug (to calm the child down if they are upset about the pain or blood from the tooth loss)
2) I instruct the child to spit out any blood and rinse out the mouth with fresh water
3) I encourage the child to rinse their mouth with warm salt water (which will help speed healing of the gum). Make sure that they don't swallow the salt water, which will be very unpleasant for them. Some children may refuse to rinse with salt water, and that's ok. It will be a good idea to let the child rinse with salt water over the next few days and couple of times per day.
4) After the mouth is rinsed out, put a sterile cotton ball directly over the gum where the tooth loss occurred (to help stim the blood) and have the child gently close their teeth with the cotton ball still in place. When the blood stops, you can remove the cotton ball. Make sure the child does not swallow the cotton ball. Bleeding should stop after a few minutes.
5) When the blood loss is contained and the child is calm, sit them down and calmly and reassuringly tell them in detail (in words a child will understand) why the loss of the baby tooth has to occur and how everyone goes through it, and how brave and wonderful they are for going through the tooth loss process.
I hope that helps!