The Brew Cabin

I'm having my first attempt at laying slabs to crate a patio area and currently there is an uneven concrete surface there. I have been told that this is a good base to use but i'm confused about what sort of mixture to use beneath the slabs. Some people are advising a completely dry mixture of sand and cement, some a semi-dry mix and some a wet mix.

I'm very confused and in need of guidance.

I advocate semi-dry, but everyone has their own personal favourite.