1. From daylight through the first 3hrs has always seemed best to me.
2. If it's a new area that I don't know, there's a lot of slow walking, sneaking through the woods. In areas I know well, I know the squirrels will show up sooner or later, so I just take a seat against a tree where I have the widest viewpoint possible.
3. Sitting with shooting sticks. Sometimes I get caught walking around and have to settle for standing and resting the rifle (hand actually) against the side of a tree.
4. Sometimes but not often. In new areas, a few barks can earn a response to tell you what direction to go in to find them. Squirrel distress sounds can bring them running to you at certain times of the year, but I've found it can also scare just as many too as they believe a predator is in the area.
5. Not a huge amount usually, but it does play a role. A little rain or snow won't matter much, but a downpour sends the squirrels to cover. Extreme cold will keep them in the nest longer in the mornings until the sun comes up and warms things up a bit. Really windy conditions makes them edgy due to making it harder to see or hear approaching danger.
6. Depends on how I found them. If I ran onto then one at a time, all 5. If they were in a group or two, I can get one out of the group and then there's usually one that can't keep from being curious and pokes his head out from behind a tree to see what's going on. Curiosity can be deadly.
7. LOL, I don't know about that, but it attracts attention of the old timers with 39As and 4x scopes (who do get their fair share of squirrels). Then I'm carrying a heavy-barreled (usually bolt action) rifle with a scope that has target turrets and a drop chart taped to the side of the stock. And apparently, carrying a range finder into the squirrel woods is some kind of taboo, because no one could possibly need to shoot a squirrel beyond 50yds. And that kind of tells you how I ended up with my screen name.