We used perineal massage and a device called an Epi-No with our first baby, and just the Epi-No with the second. DW had grazes both times, but nothing major.

The way we were taught perineal massage, for the woman to do on her own, was to insert a thumb into the vagina, and then press down and spread out the tissues aruond the bottom of the entrance to the vagina, stretching the perineum. You can also use a natural massage oil, like sweet almond oil.