Probably not the answer you are looking for but here we go.
- Common sense. Common sense is your best day to day option for protection. Not being in bad neighborhoods at night, avoiding unlit sidewalks, and keeping your situational awareness helps. Some shady looking dude seems to be walking towards you, maybe you should cross the street or leave the area. A gang of hoodlums are hanging out under that broken street light, maybe we should avoid that. Hey I can cut through this back alley to save 5 minutes on my trip, wait thats a dumb idea. I say this because most people are so oblivious to what is going on around them. You need to keep your head up and looking around. Plan out your routes so you arent in bad areas at bad times. Obviously some things are unavoidable, and just being away of your surroundings wont always work. But generally speaking if something looks sketchy its not an over reaction to assume they are up to no good. Seriously, that guy at the end of the street who is eye fucking you from a block away? Hes not asking for your number at 2 AM. The sooner you can see a threat and the sooner you can avoid it the better. You shouldn't let a potential mugger sneak up on you to where you cant run the fuck away. Which brings to my next point.
- Run the fuck away. Yes good self defense is knowing when to run the fuck away. This falls in line with my common sense point too. Shady looking guy heading your way, you change direction and he does too? Time to beat feet. You look stupid and you look like a wuss, who cares you're going home tonight. Maybe that guy was just gonna ask you for change. Whatever, you can just play it off like you suddenly wanted to build your cardio :p. Better to maybe over react and run for no reason than get mugged. Also, because you listened to my first point you shouldnt really be in a spot where something surprises you. That guy thats about to mug you? You should have seen him with enough warning where you can just turn tail and run. If he got the jump on you then you really didnt adhere to my first point (or are just really unlucky), and you need to see point 3.
- Comply. So you chose to ignore that shady looking guy walking your way and you didnt see him until he has you at knifepoint. Welp your best bet is to comply. James fucking Bond can draw and shoot faster than a guy can stab you with a knife at 5 feet, but you sure as shit cant. Drop your wallet or purse and see point two (run the fuck away). 9 times out of 10 they just want your money, and dropping your wallet or whatever might be enough of a distraction. I know its kind of defeatist, and I dont like it any more than you, but generally speaking it really is better to comply. I really hate giving in like this, but seriously it is the best option. That being said, if it looks like your about to get kidnapped or raped then you should probably start trying to get away/fight, but unless you are worth a lot of money to someone, or are in Mexico, your probably just gonna get mugged. If the bad guys dont want money but would rather just kick your ass in a senseless act of violence then see point 4.
- Self defense. Next off is some sort of martial arts training. MMA has gotten big recently and stuff like that can really help you defend yourself in case points 1, 2, and 3 fail, or if the bad guy(s) really got the jump on you. The best option here is to defend yourself, create distance, and then yup you guessed it, run the fuck away. Youre not gonna want to stand and fight. Block, create distance, run away. If you're really high-speed then you can get fancy and disarm, take down, run away. Last thing you want is to get into some sort of extended street brawl with some guy. Especially if he has buddies. You really better hope he doesnt have friends. James Bond can fight multiple bad guys hand to hand, you cant. Which brings me to point 5.
- Finally we get to weapons. Weapons are a force multiplier. If some people are really trying to hurt you, a weapon of some sort is your last line of defense. Depending on your local laws you can look into some sort of concealed weapon. OC spray, tasers, guns. Knives are just about fucking useless for self defense and you shouldnt even bother. There was a soldier on reddit a few weeks ago that told me more Taliban have been killed with bullet proof ceramic plates being used as a blunt force objects than have been stabbed to death. I dont know if thats 100% accurate but I wouldnt be surprised. When carrying a weapon all of my prior points still stand, and I can argue that my prior points are now MORE important if youre carrying. Just because youre walking around with a Colt .45 on your hip it doesnt mean youre Billy Badass all of a sudden. You cant go all neighborhood watch and head into danger. Point 5 is really really only when for when points 1, 2, and 3 (and depending on circumstances, point 4) have failed.
In your situation specifically, carry OC spray if it is legal, and just keep an eye out when your walking around. Street smarts. If it gets down to it, empty your can of OC and run away.
tl;dr: run the fuck away.
