Dimensional fabric paint will hold plastic jewels on really well, if you want to sparkle up that thong.
I would not be too sure about gluing el-wire to fabric. Having attached several strands myself to various garments and objects, I think you will have trouble getting it to hold still while your adhesive sets. The el-wire wants to go where it wants to go and needs a firm hand to make it lay down flat in the desired shape. By the time you got done clamping & fussing with it you could have sewn it three times, I am sure. Throw a slip stitch around it, wide spacing, easy to do... and then you are done. It will not pull loose on you or make a mess, either...


