1. Send cards on important days, such as Christmas, Chanukah, Valentine's Day, birthdays, etc. And don't forget to include the caregivers kids as well! 
2.  Don't just think "Oh, I really value this person!", say it!
3. Send occasional treats for all the kids in the room, and all the providers who care for them. 
4. Give pampering gifts, like movie tickets or a gift certificate to a restaurant. In households with little money, these kinds of treats can be rare. 
5. Always remember to pass on a copy of any new picture of your child. 
6. Since most childcare workers don't get paid much, pick up things you know will be useful when you see them on sale. Also, pass on coupons for items you know they use. This is especially nice for caregivers with children of their own. 
7. Pass along toys, books and equipment you know you won't need again. 
8. Send in flowers or vegetables from your garden. 
9. Try your absolute hardest to never be late picking up your child. 
10.  Never be late paying for your child's care.
11.  Give the gift of time, offer to babysitter the sitter's children once in while! 

How do you feel about gift giving at the holidays?
Not everyone feels the same on this subject, but if you're inclined towards giving your caregiver(s) a holiday gift, here are some guidelines:
 

1. Though some people feel that the equivalent of one week's childcare expense is appropriate, you may not. If you are going to give cash, whatever amount, be sure to include all the individuals who provide your child with care. It's okay to give differing amounts, but make the gifts discrete so that no one feels left out.
2. Unless you are sure it will be appreciated, stay away from gifts with strong religious overtones.
3. Consider a group gift for all the teachers, perhaps a cookie tray or gift basket for the staff lounge.