Just a couple of suggestions
Take your groomer a snack (muffins, coffee, etc) so they will know you and your fur kid is special.
Take a picture of how you want your fur kid trimmed now and how you want the hair to grow out in the future so they don't trim important things, like the top of the head or around the muzzle, too short.
Tip nicely when you pick up your kid, take a picture with the groomer and give him/her the picture framed next time you're in the area! And gosh darn you better post that picture here on YT!