The worst thing that happened to me, was I didn't get a ride until I laid on the side of the road, played dead, and an ambulance brought me to town. That was when I left an Ocala gathering, and the locals weren't going to extend any trust to me, because they saw me as a punk. Most expensive ride I've ever gotten. You would probably have better luck in that situation for me because there's plenty of creepy guys in florida that would stop and give you a ride. The other worst thing that happened to me is I got tricked into working for a gay landscaper that thought I was pretty. I lived and worked with him for 2 weeks because that's what I told him I'd do. It's like hanging out with a horny person that wants to get with you, just deflect their attempts, you should be a pro at that, right?
I had a dream that my friend was driving my truck recklessly, and I tried grabbing the shifter, it didn't budge, I tried pulling the emergency brake, it didn't stop the truck. After I woke up, I though, I should've just turned the keys to the off position, pulled them and taken them. You can literally shut down a vehicle this way and take control of the entire situation if you have a solid, full tang knife, a fierce look in your eye, and you watch every move they make. Also, on Buffy the Vampire Slayer, there was a creepy 'priest' that was murdering 'potential slayers'. He would have a monster attack them and chase them to the road, then he would pull up in his van to save the day, they'd hop in, and they wouldn't notice that the passenger door panel has been rigged to lock people in, and while they notice that, he'd pull out a wicked bowie knife, kill them, and dump them. Hope this helps you plan for worst case scenario.
So, that being said, before you get in, look at the ignition and the door that you would exit from and know that you can control those two things. Back seats have electronic child locks, so don't get into a car where you're outnumbered. And I always ask "how far are you going?" or "are you going to (name of destination)?" If they're going partial way, I decline. I'd rather wait for a ride that's going all the way than accept a ride that's going part way, and be dropped off at a terrible hitching spot (snow bank, no pull off, on a corner). When they stop to pick me up, I standby the door until they look ready for me to open it (courteously), I open it, and as I ask them if they're going to my destination, I glance around the vehicle.
Also, judge whether a vehicle is road worthy, street legal, and estimate how safe the driver is. If you walk up to the car and it has lots of cosmetic damage, this is a clear indicator that they don't care about how they treat things. Would you trust your safety in the hands of somebody that doesn't care about their own? Last year, I sold a truck to a friend, it was such a nice truck, and within a month, he trashed it. He rolled it over a snow bank, the tow truck crunched the cab and shattered the windshield, and left him with a bill, while it was still in my name. After that, I rode with him a few times, but I was always super nervous. One time, I drove that truck 1000ft down the road to get soda from the store, and I was scared, even though I was driving, I was literally scared of that truck, that used to be my favorite vehicle I've ever owned (which says a lot because I have a brand new dual sport dirtbike). Then one time, I took mushrooms with him, we went for a hike, came back to his house, and his brother came home and he was like "don't say anything!" and I was like "oh shit, oh shit, oh shit" freaking out. His brother came in and said "hey how's it going?" I was tense as concrete, and said "I need help!" and just before that, my trip was already taking a nose dive, I was thinking about death, and I though I saw it moving around me like an invisible snake wrapped around my head. My buddy got pissed at me when I blew my cover and he grabbed me and brought me outside, in the snow, I was barefoot, and he was like "we gotta go now!" and I started freaking out worse and worse and worse, I thought I was going to die, and he left me know choice, but to either run away barefoot, or get in that damn truck while it smelled like gasoline and vomit, and I just thought that God was about to shove me through the gates of hell. Anyway, the situation escalated, but while we were driving to a different location, I feared every moment that I trusted my safety in the hands of another persons driving. If I crashed, no big deal, but if I die 6 miles away from my parents house because I put too much trust in a person that doesn't deserve it, I knew I was going straight to hell, and that my parents would suffer because of it. So I just kept begging him "slow down, please slow down... SLOW THE FUCK DOWN!! oh god... s-sorry, I didn't mean to yell, just please, I don't want my parents to think they failed." Never going to take mushrooms again, not because I can't handle them, but because people can't handle me when I'm on them, people are too blind to the consequences of their own actions at this point of evolution.
Anyways, the point of that little story was. I don't trust my safety in the hands of people that are reckless, angry, rude, inconsiderate, or evil or ignorant of any sort. I require my friends even to display an indication of awareness before I even agree to visit them. That's a process I've had to refine, but it's worth it, rather than allowing my life to make the world a worse place because I died for the sake of frivolous thrills, before I accomplished any of my vision, or taught anything meaningful to anybody that may pass on the teaching to future generations.
Phew! Wow! I didn't realize I was going to dig up that skeleton.