As you know, there are several ways of playing FFR. One way is to use only your index finger(very hard), another would be to use two fingers(quite hard), third would be to use three fingers(not that hard), next would be to use four fingers(nvr tried and pretty sure no one sane has), and last would be to use two hands(a finger for each arrow[what I use]; most common among the best players). What you probably don't know is that you can challenge yourself extremely and use the following style: don't use the arrow keys, use your mouse. You can use your mouse to click the arrows in order to play the note, note that if you decide to play using this method, you'll have to click and move your mouse really fast in order to get 2 perfects on a double stop. See which one is the best for you, hopefully it will be something that doesn't make you stand out like some dumbass. Good Luck!