Use fine wet and dry paper to key the paint surface, you dont have to remove the paint, just key it, keep going at it untill its all finely scratched all over and then rub it down with good paint preperation wipes to get every bit cleaned of dust and any other greasy deposits, once thats evaporated dust over it lightly with primer let it dry (about 2 mins usualy does it on a warmish day) then repeat this untill its all coverd with primer. remeber be very very light, just want particles of paint to fall and settle on it rather than actually paint it on in full. once its all done let it dry for an hour or so then you can go over it very very lightly with fine wet and dry (make sure its wet) this will smooth out the droplets so the primer is totally smooth to touch. If you have gone to deep reapply the primer layer and rub it back down, do much wont hurt. dry the wet painty water off and use another paint prep wipe to clean it, now once thats dry and clean do the same with the red paint, usualy you can get away with putting this on slightly thicker and might not have to rub it down, depends how good you are. if nessasry let it dry then use fine wet and dry again to rub it flat. finally clean it with another wipe and give it a good few hours in the warm to harden (idealy 24 hours) then lightly apply the clear coat, this can go on in one lot working progressivly over it, start light and keep going untill its all coverd and glossy, dont let it dry between coats! just one thick layer but be very carfull its not to thick otherwise it will run and all go tits up!
once thats done.. harden for another 24 hours (or untill it stops leaving finger prints in it if your impatient like me) and whack it on the car