You will notice that you are in charge of your emotions, not the external world. You can be like a movie director who manipulates lights and sound to create emotions using only your mind.
Try to be ecstatic—adopt the point of view of an ecstatic person.
Imagine things that create this feeling. Change the tone of your voice, your internal dialogue, specific postures, and your breathing.
Once you have put yourself into an ecstatic state, try a compassionate one.
In the same way that you put yourself into the ecstatic state, adapt the steps to a new emotion.
Think about other emotions.
You can try these steps with love or any other emotion.