No control over spawning illusions
Your first skill with the scepter is a “chain” skill. It has three attacks that chain back to back and the last skill creates a clone at your target’s location. Other weapons have skills that create a clone after a skill is used once, and others will even create clones as reactions to attacks.
If you have time, this video has a lot of really good information on the mesmer for beginners. http://youtu.be/7eZ0NNd7b60
Cheers