If like myself natural and sulfate free products confuse you a little ( I did once try and research just 
exactly what sulfates are and why I should avoid them etc and truthfully got bored, I was never
top of the class when it came to science.) but want to take a step in the right direction then I do recommend trying TRESemmé Naturals Hair Care Range.

"The Naturals collection has low-sulfate shampoos, silicone-free conditioning, and natural polymers that will give your hair a more natural alternative without sacrificing performance. 
Formulated with organic Aloe Vera, Sweet Orange, and Avocado extracts, adding back in moisture 
and shine. Uncover your own naturally beautiful hair!"

I must stress that although the products within the TRESemmé Naturals Hair Care Range are not
completely sulphate free they contain a lower value, I like to think of it as a diet for your hair,
say you are addicted to cola before ditching the sweet demon you would wean yourself off it
by drinking diet cola before going cold turkey? 
And that ladies and gentlemen is probably the worst analogy of anything ever!
Anyway the selling point for me is that conditioners in the Naturals line is silicone free which
is wonderful as silicones often leave my hair with a nasty residue and lank, lifeless hair.
The shampoo soaps up well and does leave the hair feeling fresh with a lovely natural botanical scent
but for me the conditioner is the stand out product and one I do recommend if you dislike silcone
based conditioners.

TRESemmé Naturals Hair Care Range £5.49/400ml but is on offer in Superdrug at the moment
2 bottles for £6.99 - link