Rod pointed directly down at jug, tighten drag until the jug llifts, then loosen until the jug GENTLY falls back down. For my longer rods, this means I adjust from my deck, but for the shorter ones I just elevate the rod and reach up for the reel.
My idea is to get 4 lbs. of drag from the reel, not from the reel and the friction of the line through the guides plus the tip-top. I learned my lesson, believe me.
And I cannot stress enough that this is MAX drag. I use this on my MH rods and my H rod when I'm fishing in places that have musky and pike. If there's no musky or pike, I back off that, usually to 3 lb.
For M power and on down, I bend the blank under the weight of water until I reach what I consider max deflection. Then I measure that volume of water.
I consider this a good idea every time I get a new rod, because I want to know what the rod is really capable of doing. That doesn't mean that I KEEP the drag at that setting for M and lower powers, only that I test it to see what it will do. I usually back off a judicious amount when I fish. M, ML and L rods are good tools, they're fun to fish, and they can be very productive. But they aren't MH or H, not by a long shot.
I don't know about other people, but for me it's quicker and easier to reduce my drag when I'm fighting a fish, rather than increasing it. Safer, too. Set the hook with power, then back off to tire the fish if necessary.
Hope this helps. jj