Create a regular routine for him. If he knows what to expect on a day-to-day basis, he's more likely to stay on task and remain calm. This also helps when he's afraid to be without his parents; a routine helps him understand that it's normal for mommy to go away in the morning, while understanding she'll be back for him later.
Give a hyperactive preschooler a physical game or activity to play for a while to wear down their energy levels. Simply letting her expunge her built-up energy may be enough to calm her.
Provide creative activities to help usher in calmer moods and focus her. For example, have her complete a puzzle, color or play with clay. Channeling their energy into creative tasks harbors creativity and helps calm her at the same time.
Read him one of his favorite stories. Children love stories and the focus required to listen to one of his favorites may calm him. Engage him in the story by asking him questions about what you are reading.
Remain quiet and calm, yourself. Speak in a soothing voice and don't make sudden, or exaggerated movements. She may be more inclined to be led by example than word, so if you remain calm and cool, she might choose to calm down, herself. Conversely, if you're screaming "calm down," she may respond more to your tone than the actual words you use.
Emphasize the importance of good behavior by rewarding it, rather than emphasizing punishment for bad behavior. While you shouldn't do away with punishments like time-out, make the reward for good behavior worth achieving. For example, reward her calmness by giving her a colorful sticker or extra time with her creative activities.
Engage him in conversation that peaks his interests. It is important to keep the conversation calm to avoid over excitement, but talking to them about things they enjoy and relate to helps them feel independent and gives them leeway to speak their mind.