just make like a walking code, very simple, like this:
ACLS
X=0:Y=0
B=BUTTON()
WHILE 1
SPSET 0,0
SPOFS 0,X,Y
IF B AND #UP THEN DEC Y,1
IF B AND #DOWN THEN INC Y,1
IF B AND #LEFT THEN DEC X,1
IF B AND #RIGHT THEN INC X,1
VSYNC
WEND
or something like that. might have messed up the thing but you can test around.
