Summarize this article:

Once you have observed situations involving sharing, you should be able to determine which issues seem to cause trouble for particular toddlers. Is one child especially protective of a particular toy? Consider letting him or her put that toy away somewhere, off limits, during a play date. Plan to let toddlers play together when they are rested and when they have been fed. Hungry, tired, cranky toddlers are guaranteed to fight over toys. Limit play time to one to two hours for toddlers; anything longer is expecting too much from a young child. Whenever toddlers are playing together, it is best to have clear, simple rules in place. Any toys that are not meant to be shared should be put away elsewhere. All remaining toys should then be shared, with no exceptions. Consider setting a timer for popular toys, and enforce consistent limits. When a child has to give up his or her favorite toy temporarily, offer interesting replacements. If you give a toddler something fun to do, he or she may be too distracted to argue about the original toy. Generally, it's best to have lots of choices available. Have enough options around to have multiple alternatives for each toddler. Instead of grabbing toys from other children, toddlers should be taught to ask for them. Model appropriate language for toddlers: “may I have a turn, please?” If toddlers play a game that requires more than one person, whether it's a ball game or a board game, they will be less likely to fight.

Summary:
Avoid unnecessarily stressful situations. Choose your play time wisely. Set clear rules. Offer alternatives. Teach toddlers to discuss sharing verbally. Encourage cooperative play.