ok, um, i meant greasing the seals, not WD40.
to do it properly you'll need fork oil, some grease,a bucket, a few tools and about 10 mins (20 mins if you keep having to look for things the way i always do).
with the bike suspended, remove the front wheel. remove the top caps from the forks. then slide the spring out. put the bucket under the forks and undo the nut at the bottom of the leg and watch all your oil fall into the bucket. see why it was there?
repeat on other leg.
slowly slide the lower legs off the forks.
check and see that they are clean, and not full of the mud that you really don't want to use as damping fluid.
put a liberal amount of grease around the interior of the seal. this is the perfect time to check that the seals are still good anyway, so check that as well.
being carefull not to trap any of the seal, replace the lowers. replace the nuts on the end of the legs, fully compress the forks and refill with oil to the correct height (check the marzocchi site for the right height), gently cycle the forks thru a few up and downs to make sure the fork oil level is correct. replace springs and caps. wipe everything down, and replace wheel.
you just serviced your forks, and didn't use WD40.
enjoy the new and improved feel of your forks till next time.