Retention logic for simple flip flop

Hi,

I have a simple edge detector circuit and I am trying to create a Retention register strategy 

using UPF format.I have used a register for storing and restoring a value during Save and Restore.

I would like know using the register for storage is the right way ? or do we have any other method?

Please suggest me some better ways where I can use Retention logic in simple Design.

Thanks,

Kaggala