Materials: The fake ones have issues with the shoe laces being the wrong material, shoe lace caps
missing Gucci/Trefoil writing, insoles material wrong, On fake ones using velvet material (like the blue, green or red), they don't use real velvet (compare it with the red velvet ones I'm selling and you'll easily see the difference). If the pattern of the shoe is GG monogram instead, look at how the pattern is sewn onto the shoe as Gucci tries to align the pattern in a proper way (e.g. at top of toe box where it meets the bottom of first laces will always have a "GG" centered; back of shoe under back shoe tab will always have a "GG" meeting in the center. I've spotted some good fakes on here that were GG monogram but it missed those two things as the pattern was just wildy sewn on in any which way.
Outsole: On the authentic shoes, the outsole is dull in appearance and only has a shine on the top rim/lip where it connects to the upper of the shoe and the bottom of the shoe is completely dull in appearance as well. On the fakes, the outsole is sometimes too transparent or has a shiny
look. I've noticed on the fakes the outsole will either be
extra shiny (including on the bottom) or too translucent.