Make the play challenging but not frustrating for your child. Play and learning go together, especially for your toddler. Keep play light, creative, and fun. Sharing is a very difficult thing to learn. We don't expect children to be able to share until they are at least 3 years old, but you can begin to lay the foundation now.
Children probably learn best by having many good sharing experiences over a long period of time.
Set a good example. It also helps to demonstrate sharing behavior. For example, you've just cut an apple in half. There are things that I don't have to share. If there are other children in your home, your child may need to learn sharing more quickly.