The man who taught the class has a female
friend who was attacked last year in the parking garage
one night after work and taken to an abandoned house
and raped. He started a women's group and began teaching
these classes soon after. This guy is a black belt in karate
and trains twice a year with Steven Segal.
He and the others in this group interviewed a bunch of
rapists and date rapists in prison on what they look for
and here's some interesting facts:

• The #1 thing men look for in a potential victim is hairstyle.
  They are most likely to go after a woman with a ponytail,
  bun, braid, or other hairstyle that can easily be grabbed.
  They are also likely to go after a woman with long hair.
  Women with short hair are as not common targets.
• The #2 thing men look for is clothing.
  They will look for women who's clothing is easy to
  remove quickly. The #1 outfit they look for is overalls
  because many of them carry scissors around to cut clothing
  and on overalls the straps can be easily cut.
• They also look for women on their cell phone,
  searching through their purse or doing other activities while
  walking because they are off guard and can be easily
  overpowered.
• The time of day men are most likely to attack and rape a woman
  is in the early morning, between 5 and 8:30 a.m.
• The number one place women are abducted from/attacked at
  grocery store parking lots.
  Number two is office parking lots/garages.
  Number three is public restrooms.
• The thing about these men is that they are looking to
  grab a woman and quickly move her to a second location
  where they don't have to worry about getting caught.
  Only 2% said they carried weapons because rape carries
  a 3-5 year sentence but rape with a weapon is 15-20 years.
  If you put up any kind of a fight at all,
  they get discouraged because it only takes a minute
  or two for them to realize that going after you
  isn't worth it because it will be time-consuming.
• These men said they will not pick on women who have umbrellas,
  or other similar objects that can be used from a distance,
  in their hands. Keys are not a deterrent because you have to
  get really close to the attacker to use them as a weapon.
  So, the idea is to convince these guys you're not worth it.
• Several defense mechanisms he taught us are: * If someone is following behind you on a street
  or in a garage or
  with you in an elevator or stairwell, look them in the face
  and ask them a question, like what time is it,
  or make general small talk,
  I can't believe it is so cold out here,
  we're in for a bad winter.
  Now you've seen their face and could identify
  him in a lineup, you lose appeal as a target.
• * If someone is coming toward you, hold out your
  hands in front of youand yell Stop or Stay back!
  Most of the rapists this man talked to said they'd
  leave a woman alone if she yelled or showed that
  she would not be afraid to fight back.
  Again, they are looking for an EASY target.
• If you carry pepper spray
  (this instructor was a huge advocate of it
  and carries it with him wherever he goes),
  yelling "I HAVE PEPPER SPRAY" and holding it out will
  be a deterrent.
• * If someone grabs you, you can't beat them with strength
  but you can by outsmarting them.
  If they grab your wrist, pull your wrist back so your hand
  is in waving position (palm facing forward) and twist it
  toward yourself and pull your arm away.
  It is hard to hold onto wrist bones that are moving
  in that way. They stumble toward you and you stumble
  back, so you can use that momentum to bring the same out
  and backhand them with your knuckles in the forehead, nose,
  or teeth.
• * If you are grabbed around the waist from behind,
  pinch the attacker either under the arm between
  the elbow and armpit or in the upper inner thigh.
  HARD.
  One woman in a class this guy taught told him she used the
  underarm pinch on a guy who was trying to date rape her and
  was so upset she broke through the skin and tore out muscle
  strands - the guy needed stitches.
  Try pinching yourself in those places as hard as you can stand it.
  It hurts.
• *After the initial hit, always go for the groin.
  If you hit a guy's testicles, it is extremely painful.
  You might think that you'll piss the guy off and make him
  want to hurt you more, but the thing these rapists told our
  instructor is that they want a woman
  who will not cause a lot of trouble.
  Start causing trouble and he's out of there.
• * When the guy puts his hands up to you,
  grab his first two fingers and bend them back
  as far as possible with as much pressure
  pushing down on them as possible.
  The instructor did it to me without using much pressure
  and I ended up on my knees and both knuckles cracked audibly.
• Of course the things we always hear still apply.
  Always be aware of your surroundings, take someone with you
  if you can, and if you see any odd behavior, don't dismiss it,
  go with your instincts. You may feel a little silly
  at the time, but you'd feel much worse
  if the guy really was trouble.