Excellent choice for a first cosplay. Ive been thinking of cosplaying her myself, so i might be able to help. For her 2 cuffs im assuming you have clipons? If not id recommend them for that part.
For the studs at the top of the ear, since you have sensitive skin, i definitely wouldnt recommend getting piercings. Thatd be a lot of trouble just for one cosplay anyway.
What id recommend for them is to glue them to your ear with some spirit gum. I have sensitive ears myself, and ive used that method without any problem, so hopefully itll work for you too.
cosplays im working on: Tifa Lockhart(FF7) Ruby Rose and Weiss Schnee(RWBY), Kirito GGO Version, school uniform Kazuto and Mother's Rosario Kirito(SAO), Miku Hatsune default and Miku Hatsune Solitude module (Vocaloid)
Cosplays ive done: Sephiroth(FF7), Kirito SAO and ALO versions, Kazuto Kirigaya casual outfit(SAO), Homura Akemi(PMMM), Namine(KH), and Kuroyukihime(Accel World)