Hi Bill (Great Name)
Step 1
Get yourself a good music teacher (Preferably one that is familiar with Roland’s) and learn to use what your Roland really is capable of. (I can assure you that once you really make use of your Roland’s capabilities, you will only need simple styles)
Step 2
There is no step 2; the capabilities of your Roland are far in advance of anything that can be performed on a single manual Arranger. (No matter how many keys it’s got)
If you still want backing, make your own (It’s easy to do on the Roland) to play along with, forget pre-packaged or you will end up sounding like everybody else.
Hope this helps

Bill

BTW What type of music do you play?