If your pasta dough is a little sticky and some still sticks to the machine after you are done, do not use water to wash it off. Water will ruin the machine and does not wash the dough away properly anyway.
If it is not enough to just dust off the crumbs and flour with a dry cloth, use more flour for cleaning: The sticky pasta will come off much easier if you sprinkle flour on the machine and then roll as if you were rolling dough. A tooth prick might help to get into the creases to scratch out the last tiny pieces.