how to model user defined creep in ANSYS?

Hi,
Is there a place I can find explained examples or tutorials on how to model user defined creep in ANSYS?

I need to follow the creep law __>      effective creep strain (e at time t) = S. T. e^(-H)

S=(a0)^t.(sigma)^(a1) ;     T = t^(a2)+(a3).t^(a4)+(a5)t^(a6)   ; H = (a7)/[(theta)+273.16]

a0 to a7 are material constants.

I have the experimental data and tried to fit the curve in Ansys to obtain the material constants. 

I tried to follow the ansys help file steps. But facing erros messages.

If any one could give me a sample apdl code it would be helpful.

Mir

almasudme@gmail.com