The answer to that is easy: Lock your door and never leave the house
Sometimes, this is the flippant and I have to admit, uncharitable response I give to those who ask me this question. But at times, I think I'm justified. No one would ever dream of asking Tiger Woods how to be No.1 in the golfing world in 5 minutes. Nor would they even ask their club pro how to play 18 holes in 5 minutes if they were a beginner. They know they would have to spend hours at the driving range even before they get to tee off on the first hole.
In the old days, when self defence was literally self-preservation, the role of martial arts was non-negotiable..unless you wanted to die. So, as soon as you could stand, you learnt how to fight. Notice I didn't say, learn how to defend yourself. The best defence was an offensive slash, stab, kick, punch or whatever. If someone came after you with intent, it's likely that you weren't going to get a second chance to sign up for a short term course at the "Y" after that. It had to work there and then
Fast forward to the civil (or so we think, 21st century). In the age of Blackberry's and designer wear for kids, it's inconceivable that something as primitive as physical violence occurs. But it does, and you know it. From the irate person who cuts you off in the street, to the guy you accidentally bumped in that posh shopping center, we are all to aware that beneath the 100% cotton t-shirt and tertiary education, it could, in the parlance of the street..kick off at any time.
Hence, the question. And the answer to it is that there is no easy answer. Don't fall for the line which tells you what to do in 3 steps. That's what the marketing guys know you want to hear. They know that you don't want to listen to me say that it's complex, a long process, involving both the physical, mental and spiritual. No, you just want to to learn a few secret moves that will take care of every situation. And you want it fast.
I can't do that. But what I can do is recommend a good locksmith who can sell you a damn good deadbolt in 5 minutes..