Using simple serial with arduino

int potPin = A0; int potPin1 =A1; int potPin2 = A2;

One statement per line, please.

If you are going to send the data read from these pins using the letters S, B, and G, might I suggest that S, B, and G as suffixes makes more sense than nothing, 1, and 2.

int val; int val1; int val2;
int lastVal = 0; int lastVal1=0; int lastVal2=0;

Same issues here.