Jred' s suggestion is good use a drag line that is far enough behind you so it doesn' t come in contact with your boots, pants, etc. Also important to go past and loop back to your stand or location, as he mentioned. Take the drag off when in a shooting lane and comfortable shooting distance, can let it hang their.

As to scent or times, I have found that estrus and near rut (which includes late pre rut(chance phase) rut and early post rut). i really don' t see any benefit to laying down a drag line other than rut times.

I actually rarely use draglines anymore, as I prefer to hunt close to the bedding areas of the bucks come rut. If I use scents it is as a wick style, just hang in a semi circle upwind of my location.