Hi,
You need to create a Pool, and that's done within Pool Manager system.
1: create an empty game Object
2: add a component "SpawnPool" to that GameObject it will become your pool
3: Give the pool a name, you will need to reference it in PlayMaker Actions
4: create a prefab ( anything really, even with playmaker fsm on it)
5: in your pool, add a new entry ( click the plus button in the "Per Prefab Pool Options") and reference that prefab, give it a preload amount
6: now in an fsm, use the action "Pmt Spawn", reference the name of the pool, and the reference the prefab you want from that pool)
Done, press play, and you will get the pool to give you a pre loaded gameObject.
Does that help? Have you watch the videos on the pool manager website? it's important that you grasp the doc from pool manager first, before getting into using it in playmaker.
bye,
Jean