Jan C. Garavaglia describes it as:
an intermingled mix of two black plastic large trash bags with yellow circular handles, a canvas style laundry bag, dirt, green and dried vegetative material, insects, pupae, multiple cloth letters, remnants of stitching with an attached garment tag, and a piece of stretchy synthetic paper/cloth, as well as human bones. Some of the bones were recovered intermixed with this material and some from within at least one of the black trash bags.
(BBM) So some of the bones were inside one of the black trash bags.
Then later Dr G says: Present inside this laundry bag are two fragments of black, gnarled plastic consistent with the black trash bags which were found entangled with this laundry bag.
Trash Bags:
The two plastic bags that were intertwined with the laundry bag and the other assorted leaf and vegetative material consist of a cinched trash bag at least 36 inches in length (bag was left cinched), while the other is an untied bag approximately 40 inches in length.
Both bags have a yellow plastic attached cinch tie. The one that is tied is tied with a single loop and two loose ends.
(BBM) So this sounds to me like Caylee was wrapped in the blanket (which Dr G later describes in the report), then placed in a black trash bag, the top was cinched shut, then placed into another black trash bag which was not cinched shut, then placed into the canvas bag.
Gary Utz, Deputy Chief Medical Examiner, describes it in his report as:
" . . .a jumbled mass of two disrupted black garbage bags with yellow handle ties, a cylindrical fabric laundry bag, leaf litter, vines, soil and debris.
John J. Schultz, Ph.D., Assistant Professor of Anthropology UCF says:
On December 11, Dr. Utz and Dr. Schultz separated a light colored laundry bag from two black garbage bags with yellow pull ties. The two black bags were torn in multiple places and intermingled, and were partially within the laundry bag. The laundry bag contained a rigid metal rim, as seen on x-ray, around the opening. The black bags were positioned on top of the metal rim while a fold of the laundry bag was visible overlaying the top of the garbage bags.
<snipped>
In addition, although the black bags were torn, two hand bones were removed directly from the black bags.
(All Bold by me)
So I think she put her inside the bag, cinched it up, another bag, and then stuffed her into the laundry bag.
IMO