None of us will do things that we do not feel benefit us in some way.  In other words, we need motivation.  This is true for any individual.  Our role as the adults working with the learner is to figure out what is motivating for the individual.  For the sensorimotor learner, we need to determine which of the learning pathways (vision, hearing, touch, taste, smell, or movement) provide the most usable information for the learner.  We also need to make learning fun and interesting!

You may want to make a list of things that the child is attracted to or likes and things that he shows no interest in or rejects. This may help to give you ideas about what motivates him or her to engage. Does your child have a favorite color, toy, or movement? What things does your child show an aversion to or reject outright? Start with things the child is interested in and later on you can introduce less preferred items. Sometimes the lack of interest or rejection is due to lack of experience with a sound, texture, smell or other quality the object possesses. 

Also, consider any self-stimulation your child exhibits. These may give you insights to what is motivating for him or her. For example, if your child likes to flap his hand in front of his eyes when left alone, he might be motivated by the changes in the light pattern or he might simply enjoy the feeling of that movement on his hand and wrist. What could provide interesting changes in light? Perhaps mylar paper, mirrors, spinning pinwheels, or balls that light up when squeezed or moved. What toys might provide interesting auditory or vibratory feed back when held and moved in a flapping motion? Perhaps a rattle, a rainstick, a disposable aluminum pie pan, or a string of wooden beads.