I did my level 3,
Unfortunately I cannot advise too much, as I went straight for my level 3 upon completing level 2.
I can however say, I really enjoyed it!
one of my old managers did not do level 3, and I taught him a thing or two from it! I think its brilliant for expanding your experience, and I feel that my level 3 gave me a lot more knowledge than level 2 did, especially with all the in depth colour correction stuff.
I felt level 3 was also mainly about being creative, well no body can teach you how to be creative, I feel that comes naturally. When you can look at a standard style, and turn it in to a whole new look after a couple of hours of colouring and cutting, this sort of creativeness happens every day when your a hairdresser. I do feel though that Level 3 helped me to separate creative from plain stupid.
Watching some of the girls I trained with giving Pale client black hair, or Cutting a pixie cut on a client with the wrong shaped face was horrendous, Level 3 taught me not to be stupid where creativity is concerned.
Enjoy every second of it!xx