Wow...some of this stuff I am reading I'm not sure i agree with BUT to each there own. Here in Easton Maryland we don't get the best duck hunting, but geese we have, and that's what I have grown up on. Few things I learned and figured out.
Geese are not as predictable as some experts might like to think. Some days, no matter how good your spread, blind, or calling, they just have something else in mind. Frustrating? Yes. But its how they are programmed. The next day with the exact same conditions you might be limited out in 20 minuets. Its happened too many times to count.
The moon does play a major part in how we hunt here. Full moon, the geese are normally active and feeding in the fields, which is when we set up on the water and ponds to kill them as they come to sit and digest in the mornings, then switch up and catch them heading back to the fields during the evening. Dark of the moon obviously is the opposite.
I have killed ducks over decoys that look more like pieces of drift wood then decoys, geese however don't fall for it. Granted Easton MD, is heavily hunted and the birds are educated easily, but still, clean well painted decoys are becoming more and more of a must when it comes to goose hunting. All are decoys are flocked and gently transported.
Motion is a big one as I'm sure you know. We mix GHG shells with motion stakes in the middle of our decoys, you wouldn't believe how just that makes the entire spread look alive.
About everyone I hunt with has a call around their neck but only a handful know even the first thing about calling. You would be surprised what knowing a few basic sounds such as the cluck and moan will do for you. Read the birds and how they react to the call. Some days high pitch non stop calling puts birds in your face, but more days then not just a few well placed sounds will work to your advantage. Of coarse that being said, there have been plenty of days I have never touched my calls and done just fine. As a side note, I'm not so sure about the "only call at birds when they are heading away" but i do know that we make sure we are quiet when the geese are directly over head or any place where the call will help them locate the blind or pit. Layouts we don't worry as much because we are right in amongst the decoys.
The flag in the field is just as important as the call. Geese see too many spreads just like yours and that quick flapping of black is more unique and spells natural and relaxed all over it.
When I kill my geese, I normally like to get out quick and let the least amount of birds possible know that i was there.
Don't fall into the trap of thinking you HAVE to shoot 3 1/2 to consistently put geese down. I own a 3 1/2 capable gun and only shoot 3 1/2s over open water rigs. I guess this is more of a preference then a tip, I just see too many people spend unnecessary cash on shells that simply are not needed on decoying birds in a field.
Bring a dummy for your dog (if you don't have a dog, a small child will suffice)
If your not seeing birds, toss it out in the rig and your guaranteed to have geese magically appear.
I haven't looked over this so i hope it is at least semi legible
I think that's only 9 but ill leave it at that. A lot of goose hunting is just getting a feel. Good Luck