Need to know how to make an Ardino position controler for a lineria actuator

I would like to know how to use an Arduino to make a Lineria Actuator stop at seven specific locations. The actuator will be attached to a board which in turn is attached to ball bearing drawer slide. I want to be able to use a computer to define the points where the actuator will stop. I need to be able to select the point I want the Actuator to stop. I have no clue where to start. I have assembled electronic kits in those cases I was working from someone's plan. Here I don't know where or how to begin, so can someone help me get started with my project?