Do you add formula or water first to bottles?

First time mom, and please no nasty comments:

My daughter is 7months old and I just realized I think we have been making her bottles wrong. I was shown by my inlaws to scoop in her formula, THEN add the water. So for a 6oz bottle: add 3 scoops first to the bottle, then add water until it reaches the 6oz mark. Even after we shake/mix it the end result is still 6oz.

My daughter is perfectly healthy and growing as she should but have I really messed up? Do I need to add the water first and THEN the formula? Is it too concentrated if I do it the way I have been, or why does it matter?

Does anyone else add formula first and then add the water?