Right then! Tis done!
The shampoo:
Definitely need to shampoo twice. The first application didn't lather up but the second one did. God knows what's in it but my hair has never been so squeaky clean! I gave it a good comb through beforehand as my hair without a ton of conditioner is awful. It combed through afterwards ok though.
I left my hair to dry on its own while I got on with a bit of tidying up then gave it a blast with the hairdryer.
Application
After doing the first section with the brush provided, I binned it off, just scooped some on my fingers and slapped it on then combed each section. It doesn't smell but did sting my eyes a bit. Didn't take as long as I thought ( probably due to slapdash method)
Drying
Took about 20-30 min. Didn't style it, as knew it was going to be straightened. Felt very nice and soft, even at this stage.
Straightening
Again took about 20-30 min. Easy enough to do. Hair gets very hot but I always straighten using a comb.
The finished look 
Well it's smooth, straight, and very shiny. But sorry oreo it does look flat as it has been straightened within an inch of its life.
I do look like Morticia (Sp?).
I figure though, as I'm going to wear it either curly or tucked behind ears/fringe clipped back I can do this now and just straighten it at night.
Can't wait to see if it's actually worked in 3 days time or if I'll be back to the Anita Dobson look. I'll let you know!