I got this idea from a small boutique in our town a few months ago. A dry erase board for babysitter notes. Why haven't I thought of this before?! Brilliant. You write all of the information that isn't going to change right on the paper, then stick it in a magnetic frame and use a dry erase marker to write what time you should be home and any special instructions (what to have for dinner, bedtime routine, etc.) If there's an emergency or if the babysitter has a question, she can simply refer to this.
Feel free to print mine, or create your own!