wavy hair?

[ph0tobooth]

My natural hair is slightly wavy that I used to be able to get fairly curly before. Lately all I've been doing is straightening my hair and now when I try to wear it natural it just lays flat and there are hardly any nice waves to it. I was wondering what the best products are,  to bring out the natural wave/curl in fine and thin hair. I'm looking for a product that can make my hair not too curly but just wavy enough :)

any help would be appreciated!

And also, has anyone tried using apple cider vinegar as a toner (diluted with water of course). Does it work for you?

Thanks!