Back in the day it was a rule that the delts (shoulders) should be much wider than the waist in order to form that V taper. This was the goal of every bodybuilder back then. This is what all of us strived for and it took a lot of work because genetics wasn't so kind to everyone.
Structure played and important part as some people are just born with naturally wide shoulders and small waist. I don't have a with a wide waist but I have large abs and they have a tendency to grow big, which makes my waist look larger.
Steve Reeves in a suit
Arnold also had the structure of sloping shoulders which made him look round shouldered and he had to work hard to bring up the lateral delts in order to widen them out.
Keeping the waist slim and tight to off set shoulder development is also tricky because you can work your abs so hard, ( like I did mine) that they get thick and overshadow the width of the shoulders. One exercise I tell everyone NOT to do is side bends with weights. This also widens the oblique muscles around the waist and even though you think you're reducing it, it's actually getting bigger. So then you work it harder and it becomes a vicious cycle.
However wide shoulders can be achieved if attacked properly. Years ago it was thought that behind the neck press was the best way to develop the delts. We all did them and there was a man in our gym that could actually do them with 315 lbs. That's really strong and he was thick and big, but his waist was twice the size of his shoulders.
Over the years it was discovered that this exercise caused a lot of shoulder problems and arthritis because it's a very unnatural movement. At this point in my life I can't even get my left arm back to grab the bar from doing these.
Many of us found alternative exercises to do in place of it, such as the standing press with a bar, alternate dumbbell presses and smith machine press and all three works very well.
Basically the pressing movements added thickness and size but didn't do a whole lot for the shape of the muscle. There are three heads, 'anterior; (front), 'posterior', (back) and 'lateral', (side). Each one has to be specifically worked separately in order to get maximum size out of it.
Standing laterals for the side, bent over laterals for the rear, and front raises for the front, but bench press also works the front and sometimes will increase the size ratio to the back so be careful and work them evenly.
Back in those days, I also found that one arm dumbbell presses twisting as you press up really worked well. I had very good results with that, using one arm at a time. We always experimented with movements to see what worked best. I guess you could call us the pioneers of the game.
Supersets with standing Dumbbell presses alternating with standing lateral raises works extremely well and gives your delts a very good pump. 4 sets each and then finish off with 4 sets of bent over laterals and 4 sets of shrugs.
I've saved the best for last and this one will really blow your delts up. Arnold and I experimented with these plenty.
Start at the 20 lb. dumbbells and pick them up for standing press, with palms facing you. As you press up, rotate your palms out to be facing front. Each rep should be exactly like this. After your first set of 8 reps, make 5 lb. jumps and work your way up as far as you can go non-stop. We went all the way to the 80 lb. dumbbells.
This is a killer and you're not done yet. Rest for a few minutes and then start where you left off and do the same thing all the way back down the line. This is all you need on the pressing movements. Now grab the dumbbells again and do a set of lateral raises, and do at least 8 reps. go all the way up the rack again as far as you can go. Your reps will drop but that's ok, as you can make them up on the end. Once you get to the top, rest then work your way back down the rack.
A lot of people over the years have adopted this movement and call it Arnold presses however we thought it up in the gym as we were training. It was just one of the many things that we did and it seemed to catch on.
You won't be able to do this work out more than twice a week as its really depleting and needs some good recovery time. In fact you may just want to do it once a week at first and then see how it goes.
Workouts like this cannot be done for long periods of time such as a month tops and then change it. Your body will adapt to it and then it will need a change in order to grow again. This is with any routine, but this one for sure.
Try this and watch your delts grow in front of your eyes and be sure to eat right and take your supplements. This all figures in to make you the champion you deserve to become.