1. Never brush your teeth or floss before giving a blow job. Brushing and flossing open your mouth to cuts and bleeding. If you feel you need to brush then do it at least an hour before play time, or use a mouth wash. Mouth washes are clean feeling and germ fighting.
  2. Some men use a stay hard cream that allows them to stay harder longer by desensitizing the penis. This is ok for hand jobs and intercourse but many of those creams have Novocain in them and the woman’s mouth can go numb.  Let her know if and when you use such a cream. 
  3. Also with the creams do not use the sweet tasting ones because they may contain sugars which can lead to yeast infections. This also goes for mints.
  4. Things like Chloraseptic sore throat spray, sprayed in the back of your throat can also ease the gag reflex. It numbs the area just enough.