Basically you hold the leash handle in one hand and cinch down on the leash with the other.
You give the dog 6-10 inches of slack. Your cinch hand stays firm and close to your leg. As the dog tries to walk in front of you, you keep your pace and step and since there is not enough slack, the crossover attempt is met with awkwardness and knees.
If the dog tries to go the otherway, its ass should be bumping into your knee. Again, its super awkward for the dog to have it stride all fucked up. Every time it tries to do something, like bolt, jump or veer away from your step, it just feels weird to the dog.
As you walk around, pay attention to the dog. What is it all excited about. Well, take the dog to go check its pee mail. Yep, let it sniff around bushes and lawns all it wants as long as it looks like its looking for a place to shit or piss. If the dog just pissed for the 30th time and ain't even squirting anything out anymore, no big deal.
Why is it no big deal? Well, by the time you make it to the end of the block, your dog pal feels like he took the longest most exciting walk ever.
Anyhow, because you have the leash so short, the dog is figuring out what feels cool and what sucks pretty quick. This is the most important part of this whole thing... DO NOT YELL, COMMAND, DISCIPLINE OR JERK YOUR DOG. Yeah, at first you are going to get frustrated that dog man ain't being chill, but you don't need to be the one that fucks it all up by getting mad. Play it mellow.
Dog tries to bolt, just stop. Hold the leash with a firm arm down your side so the dog is by your knee. The dog doesn't have to sit or lay down or anything otber than just kind of mellow out. This may be hard to believe, but the dog will over about 5 or 6 walks, start to mellow out.
When you need to turn right or left, move the leash that direction. Want to go left, move the leash left. Want to go right, move the leash right. The dog will catch on pretty quick.
After a few walks, let the leash out a few extra inches so the leash has a little more slack. Don't let the dog know you are doing it. You have to be kind of sly. Cinch the leash the same way, slow and firm where the dog shouldn't notice really. What you are doing is teaching the dog to get used to having less tension in the collar and more slack on the leash.
Finally, start the walk with a cinched up leash and slowly let out all of the slack and watch dog just kick it with you. No bolting, crossing, wandering or barking. Just strolling.
Notice how I didn't really mention anything about barking or jumping or anything like that, because a shortleashed trained dog is more about learning to hangout and be chill than all that shit like discipline and orders. Fuck that.
You want an uptight wimpy dog that constantly looms to you for approval? Yeah, discipline and orders are the way to go.
You want a dog that is basically indifferent to you as a person and is only into what you can give it, try the reward system. "Dur herr, uh, my dog does tricks for snacks." you know who else does tricks for snacks, prostitutes. They don't care about you. They just want to roll over on their backs for the rewards.
Do the, "Look man, lets not make this all weird and fucked up. Pay attention to me and I will pay attention to you." method. You learn what the dog wants and needs and how the dog communicates and homedog will be stoked to have you as a guy that feeds him and puts water in his dish.
Funny thing is, take the same attitude and apply it to roommates and it works exactly the same.