Making a sticker chart

So I have been given a challenge. I need to make a sticker chart for my girls. Now its not a chores chart necessarily but a chart to get them to do behaviors I want. The behavior I have decided to do:

Rachel is: Doing what told when told. So what will happen is everytime she does something as soon as she is told to she will get a sticker. Once she gets 5 stickers she will get a special prize.

Charle is: Sharing her toys. So everytime I see her share a toy with a friend or her sister she will get a sticker.With her once she gets 3 stickers she will get a special prize.

If they dont do what I want they simply wont get a sticker but I also wont be taking one away. We are starting it in the morning so we will see how it goes! Im really excited to see how they do with it :D