In case you were unaware, it's usually referred to as the seven years War outside of the US.

Oh boy, this is a part of what I'm doing for my undergrad thesis. The relations between Whites and Indians was a really complex ordeal.

Okay, so, it kind of depends on what part of the war. During the Braddock campaign in '55, Indians were used as scouts for the most part. Braddock was a bit of a stuffy Scotsman and didn't really bother to listen to his Indian allies about the impending ambush from the French-allied Indians up ahead. He fought European style, and in the woods of the Pennsylvanian backcountry, that didn't mean jack shite. Indians fought in a style that we would call "guerilla warfare" today. It's not an apt description, but I think it does the best job to describe it in modern day terminology. Otherwise, it would be called something along the lines of fighting like an Indian. Instead of lining up and waiting to get shot, they would hide behind bushes and trees, take a few shots, and either gtfo or charge in if they did their work well enough.

Now, the British learned fast that they needed to shift gears. The Forbes Campaign was drastically different than Braddock's, as he was a little more lenient with the Indians. In fact, he wanted make his soldiers into "Indians." This not only including fighting using Indian tactics, but dressing like them too. The British recruited rangers from the Pennsylvanian (and Virginian, etc.) back country, because they were the ones used to fighting with Indians already. James Smith's journal made note of "American riflemen" taking fire and scattering in the woods like Indians. Thomas Barton, an Anglican minister that was following Forbes' campaign, noted the mix of Regulars, provincials, and Indians within the companies. He also saw them drilling and exercising in "running & firing in the Indian manner." Sometimes it got the point where the whites blended in so much and looked like their Indian counterparts that they had to distinguish themselves with yellow bandanas or sewing Union flags on. Interaction between Indians and soldiers was quite common, and Indian clothing was a popular item to trade for.

Using Indians as scouts was common, but they were also part of fighting parties. They didn't like the whole "lining up" in formation and often stuck to their own ways of warfare. There's no record (at least that I have seen) of any Indians taking command per se, as the British liked to assume most of the control. However, the alliance with the Indians was viewed as important. In the White-Indian war parties, the British and the colonists often "deferred to the Indian desires, methods, and directions," so in a sense, the Indians did take control when it came to fighting.

Now I gave you mainly a British context (and a Pennsylvanian one at that). There's a much larger scope at hand. I couldn't say how it was over in the French side, as it was vastly different and I'm not even going to pretend to be an expert.

"Crucible of War" was a good book. Try "Breaking the Backcountry" by Matthew Ward, if you want a more in depth look at White-Indian relations during the war. Also check out James Merrell's "Into the American Woods." A lot of the primary sources I used came from the writings of General Forbes, Washington, and Bouquet themselves, along with a few other journals from lesser folk.

If you need any clarifications or any other questions, please ask.