Thinking about traveling solo?  There's no reason why
you can't enjoy a wonderful holiday on your own, provided you
take a few precautions to ensure your safety while away from
home.
Travel Light:
The fewer bags you have to manage, the simpler it will be to
maneuver through crowded airports and the less likely you'll be
to lose track of your belongings.  If possible, keep your
luggage to one wheeled bag and one carry-on tote that can be
attached to it.  If possible, avoid carrying a shoulder
bag, and instead, put your wallet and passport in an internal,
zippered pocket in your tote.  Make things as difficult as
possible for would-be pick-pockets.
Choose Your Cabs With Care:
Don't practice your cab hailing skills in foreign
countries.  You might just catch a whole lot of
trouble.  Instead, ask the concierge at your hotel to
arrange for a reputable taxi company to pick you up.  If
you need a cab from the airport, ask a uniformed airport
employee to show you which of the many cab companies vying for
your business are actually licensed.
Keep Your Map Out of Sight:
There's nothing that screams "tourist" more loudly than an open
map. Do your map studying in the privacy of your room, before
you head out so you'll be able to proceed confidently and keep
your eyes on your surroundings.
Put Your Hotel's Business Card In Your Pocket:
If you get turned around and can't find your way back to your
hotel, find another woman and show her the card.  She may
be able to help you get reoriented.
Bring a Doorstop and Smoke Detector:
Before leaving home, go to the hardware store and invest in a
simple rubber doorstop.  After you've locked your hotel
room door, slip it under the jam as an extra bit of protection
against anyone trying to enter from the hallway.  A small,
portable smoke detector is easily set up in your room just in
case the hotel isn't properly equipped.
Leave a Note:
If you're venturing out on your own for the day, leave a
detailed itinerary of your plans in your hotel room and tell
the front desk what time you're expecting to return.  If,
for any reason, you don't come back on schedule, you'll have
left a trail for others to follow.
Stay in Touch:
Send emails and/or phone home regularly to let friends and
family know what you're doing and where you are.
Stay Safe:
Ask for a room on an upper floor, so you won't have an easily
accessible terrace or balcony door, and always request a
location as close as possible to the elevator. 
Trust Your Instincts:
Don't like the looks of the gentleman in the elevator? 
Make an excuse and don't get in.  Trust your instincts
even at the risk of seeming rude.
Lighten Up:
Pack a small flashlight in your purse.  Some resorts have
pathways that are very poorly lit at night.
Leave the Bling at Home:
Flashing expensive jewelry is an invitation to be robbed. 
Leave your valuables at home and be safe.