Hi Aimz
There is some research that suggests that perineal massage can reduce the chance of tearing. A few other things that may help are:-
Do not birth on your back.
Birth the head slowly giving yourself the chance to stretch.
Only push when your body tells you to and not when the midwife/ob wants you to (coached pushing).
Visualisation may also be helpful. As you start to feel the burning down there try to “see” your vagina stretching to make room for the baby to slide through.