“Feeling safe isn't the same thing as being safe. Feeling scared doesn't necessarily mean you are in danger. It means pay attention.” - secessus

Emotions are information, not instructions. Gauges, not guides. – anon

There are at least three broad categories of threats to consider:

1. unsafe choices, likely, but people ignore it.
2. property crimes (vandalism, burglary), unlikely, but people worry about it.
3. violent crimes (robbery, assault), exceedingly unlikely, but people freak out about it.

No one but you can address whether or not you feel safe. That occurs solely between your ears, and can gut your life. As far as being safe:

• A charged cellphone with coverage in the area may be the most important piece of safety equipment.
• maintain situational awareness
• areas of lower population density are safer from violent crime than cities. Lowest violent crime rate would be boondocking out on your own somewhere. Caveat: property crime rates increase in rural/underpopulated areas. It is unclear if this pattern extends to remote camping areas.
• park in such a way that you can pull out without backing
• be aware of multiple exit routes
• if in a restaurant, etc, sit where you can see the van from your table
• get a carry license if you are so inclined, and have the discipline to know and follow relevant laws. If you have never owned or shot a gun before this probably isn't the time to get one.¹⁾
• get a dog. Even a small one works as an alarm
• leave the drivers' seat clear of stuff so that you can get in it without delay²⁾
• put your keys where you can find them easily and always in the same place.³⁾

In the wild:

• avoid camping in or beyond desert washes. The water can rise suddenly in your camp, or block egress from the camp.⁴⁾
• Similarly, avoid camping in low areas where runoff might collect from higher ground.
• carry extra food and water in case water or mud makes it impossible to get back to town. It will dry out in a day or two.⁵⁾
• be ready to break camp at a moment's notice if needed. This means deploying nothing that requires work before leaving: awning, lawn chairs, bbq, tilted or portable panels.⁶⁾
• scout out another way out of the campsite in case the primary exit is blocked⁷⁾
• Be aware of where you put your hands and feet: know what poisonous insects and snakes live in the area
• store, cook, and eat food in a safe manner in bear country

In populated areas:

• park facing outwards so that you can put it in to drive instead of having to back out of a parking spot⁸⁾. “Pulling through” to the further spot can make this very easy.
• be aware of driveways and other access needed by other drivers
• side-to-side⁹⁾ sleepers may want to sleep with their head on the curb side to limit injury from vehicles hitting your parked vehicle
• park under street lights
• avoid neighborhoods where there are bars on the windows

You don't have to be a meterologist or stormchaser, but a basic awareness of upcoming weather and flood/fire conditions is important.

Techniques:

• looking at multi-day forecast in your area
• if you stay in one area, you may want to leverage the community's text/email/phone alert system, or configure a weather radio to receive alerts
• watch for smoke plumes that could indicate wildfire

Additional tips that may be helpful for solo female travelers:

• choose parking areas that are NOT in large metropolitan areas but rather in smaller urban communities…lower crime rates and more upscale neighborhoods.
• sleep in something you can drive in suddenly if needed, without the need for additional coverup