SAND UR WHOLE CAR........NOT TO BARE METEL BUT TO CLEAN IT UP.....UR GONNA SAND AND ROUGHIN THE PAINT.......(IF U DONT SAND UR CAR AND JUST SHOOT PRIMER OR PAINT THAT SHIT WILL NOT STICK)....... JUST SAND THE WHOLE CAR WITH A 150 GRIT PAPER........... BUY A GALLON OF HIGH BUILD PRIMER AND PRIME UR CAR, THE WHOLE CAR......PAINT STICKS BETTER TO PRIMER THEN TO OLD PAINT..........PLUS THE HIGH BUILD PRIMER WILL GET RID OF ALL UR LIL ROCK CHIPS AND SAND SCRATCHES.................WET SAND THE PRIMER TO SMOOTHEN IT UP , USE A BLEND PREP WHEN DOING THAT...........THEN PAINT......................................SO JUST GET A GALLON OF PRIMER,1 QUART OF REDUCER, AND 1 QUART OF ACTIVATOR, AND 1 GALLON OF PAINT....