I would suggest you select style and tempo and any other adjustments such as harmony, intro etc...
When you are happy with the sound, THEN save it all to memory so that you can recall it later on.
When you recall it later you can still make adjustments to your playing and change the the style and tempo but the memory settings will cut off.
You can recall the memory anytime.
You need to follow the instruction manual to show how to set a memory. It maybe as simple as holding down the memory button and asigning a bank and key. That is how I do it on my PSR S650.
cheers
Ray