Hi there BiggLJ
WELCOME to the forum!
Well, I don't know what features you have or don't have. There's a lot more to consider when it comes to hairstyles besides hair's density.
But no matter, you say you already have longish hair and want the longer, wavier Troy hair. I think you should try a
body perm. They use pretty big sized perm rods (I'd say alternaating peach and white) and when used on longer, especially all-one-length hair (and all-one-length is the important key) it will produce not only the waves you'd like, it will plump up those thin strands. Trust me, I know as I too have thin hair.
Go to a stylist you trust! Make sure your hair is all-one-length...preferably a little longer than in this picture as the wave will make it shrink a little. See, if your hair is layered, the perm will result in too curly a style and I don't think you will like that!!!! Make sure the stylist is trustworthy as you don't want them "over-processing" your hair or damaging it. Thin hair is usually fragile, so you want them to do right by you. Ask him or her about protein treatments and "porosity control" packs which the latter, can and should be, applied immediately prior to wrapping the perm.
THEN, MAKE SURE THEY T - R - I - M your hair AFTER the perm. This way the ends are clean-cut and blunt. Trimming before results in perm solution soaking into fresh cut ends too quickly with a frizzy result. Always best to trim it AFTER. And yes, I emphasize TRIM. After all, you just want it even, blunt cut and looking good, right?
Oh and btw, LISTEN to them when they say wait at least 24 hours before shampooing right after a perm. You could wash away your perm!!!! And don't worry, the smell will wash away mostly in that first shampooing. If not, it will be by the second shampoo!
Hope this all helps and I do encourage you to go for it.
