How can i secretly buy a thong?

Okay , So im 14 and i wanna get a thong... Don't think bad of me i juss wanna try it out . The thing is i don't know how to hide it from my mom ? I Have the money , but i don't know how to secretly buy it... Or hide it and stuff you know ? ( Like in the store ] Any adive / Suggestions ? Please Help (: Oh and any suggested places i should get one at ?