if your looking to do a cheap touch up repair as already said get a touch up kit and carefully fill the stone chips in
there are various methods to actually getting the touch up paint where you want it a popular method on small chips is to use a cocktail stick rather than the supplied brush
if the car has a clear coat and the clear coat is supplied with the touch up kit as well as the colour, pouring a little out of both ( touch up and clear coat ) into / onto something and mixing them together before you apply the paint to the chip can give good results
once your happy with the freshly painted stone chips and the paint has dried using a bit of scratch remover / polish can blend the chips in for a better finish
takes a little time but it's cheap
don't bother with rattle cans unless you are quite confident with them, the chances of getting a colour match off the shelf is almost zero and wherever you spray it will show a mile off
you could try one of the car paint suppliers that make up rattle cans to the colour of your car but by the time you have finished with sanding / prep and primer you probably heading towards the cost of a back street garage giving the bonnet a quick spray
keep in mind a bonnet is quite a large area and to tackle one with rattle cans in all but perfect circumstances your gonna struggle ( slightly better chance with made up cans ) the spray pattern is small and the amount of paint you can layer on without runs is pretty thin
buying a compressor and all that goes with it just to spray a bonnet is not really an option financially unless you intend using it for other purposes
you could wrap the bonnet which hides stone chips rather well
did this myself on a bonnet ( took 2 attempts
) with carbon wrap but ended up fixing the stone chips with a carbon bonnet instead
for stone chips i would go the touch up method
it's cheap and can give pretty good results if you get a good colour match and can flatten the touch up to the existing paint it looks far better than trying to spray over the stone chips with a rattle can
iv'e even considered getting another same colour bonnet from a scrappers before now but you have to get it when the car comes in before it gets damaged by the usual scrap yard antics or it will end up worse than the one you already have
done a lot with rattle cans over the years, great for small items not so much for large areas
