If you are raped, do not touch anything, change your clothes or wash immediately afterwards. Call the police, someone you trust - a friend, family member or doctor and ask to be taken to a hospital. The hospital staff will provide medical assistance and a doctor will collect evidence that can be used in a court if the rapist is prosecuted.
If you are threatened with rape and there are people nearby, screaming, fighting back or running may improve your chances of escape. Other than that, it's impossible to make specific recommendations. A woman must assess her own situation - the circumstances and each offender's reactions will be different. See also MUGGING