Why do you need a step-by-step proceedure? You have already done one in HFSS, but just using a different material.
Don't know the LTCC material to use? Ask your vendor for specs on the FIRED materials that he uses. Select the one that meets your criteria.
When designing with LTCC, just remember to design with PRE-FIRED dimensions, but simulate with POST-FIRED dimensions. (Or develop the patch you want, then add the LTCC shrinkage factor to the design for your vendor.)