...//... inquire as to how to correctly (I know there are different ways to do it) sling a pony? i have seen some vidoes out there but would love to hear how you all sling? ...//...
Landlocked123,
Took a while to come to terms with a slung pony, much fussing with it. However, once fine tuned, there are many benefits to slinging. A properly slung pony becomes just another something that you can take or leave behind as needed. It is also, as Uncle Ricky pointed out, easy to pass off to or clip onto a needy diver. This capability should not be undervalued by a new diver who hasn't yet taken rescue but is in the constant company of other new divers.
You asked about rigging a slung pony. Here is how I do it:
First, you need an easy deployment. I get this by keeping the secondary under two innertube straps, allowing you to just pull the secondary reg to completely free both it and the entire length of hose. Once deployed, it is quickly re-stowed under the round bungee that prevents the SPG from moving and releasing its hold on the secondary reg.
Note top view, keep everything tidy.
I use the SPG's hose to capture the mouthpiece and keep the secondary in place. -look carefully at the top view to see this.
The neck ring is usually metal, I replaced this with a urethane drive belt sized and sealed it to make a ring that just stretches over the valve. Use 1/4" round solid urethane drive belt from McMaster Carr if you wish to go the same way. The bottom clip also has a urethane ring. I clip this to a tailpiece rather than my waist D-ring, keeps it tucked in closer, less drag. The urethane has an added advantage of making the entire rig cuttable.
The bandclamp rides over a length of 1/2" vinyl tubing slit open along its entire length. This keeps the bandclamp from damaging the tank or causing corrosion in saltwater due to dissimilar metals in contact.
Last step is to fuss with bandclamp positioning to get the valve to hang where you want it while keeping the pony tucked in close to you yet out of the way.
Stay safe.