To keep a long wig from tangling/matting/clumping in the nape of the neck or back, you can spritz it with a leave-in wig conditioner before wearing it. Comb through your tangled wig to fix a matted wig. But don’t overuse wig products. It will lead to clunky build-up and uncleanness. Mousse and other lightweight styling products are better for synthetic wigs.