Its ok, I have worked it out.
I see it is quite easy to just do (x-a)^2 - 2(x-1) -3
The constant has no effect on shift on x axis.
If I have y=x^2 then to shift by 1 on x axis I just do this: (x-1)^2
But due to constant expression I am a bit confused.
The only way I can see to do this is to factorise and then shift factors 1 to the right.
Eg factors of x^2 -2x -3 are (x+1)(x-3) to transform by 1 just add one to each factor: ie becomes x(x-4) - then expand out to x^2 -4x.
Is that the easiest way to do it?
Just checking I am using the best technique.