I posted here earlier in the week and some kind souls pointed me in the
right direction, clarifying what I should lay my patio on. But I need a
bit more clarification please.

After whacking down my sub-base I am putting down a drymix mortar to lay
the slabs onto. It seems one part cement to four parts sand is the right
ratio - correct? I had read that the sand for patio work should be sharp
sand (as it 'locks' in place) but I see that pavingexpert.com recommends
that soft sand be used for mixing up mortar. Which is correct? If it
should be soft sand what would the result of using sharp sand be? I have
already ordered the (sharp) sand. I went through what we wanted to do
with someone at the builders merchant and he seemed to agree that we
were on the right track, so hopefully this is not our first stumbling
block.

I was also recommended to put down extra cement at the sides of the
patio to keep the sand in - should this be pure cement (put down dry, as
the mortar?) or just a mortar mix with a higher ratio of cement in (if
so what ratio).

Apologies for the dumb questions but this is all new to me. I have this
week off work this week to do this - I want to be sitting on the patio
having a beer by Friday. In any spare moments during the process I also
have to decorate the kitchen........

Many thanks,
Iain