I was recently studying [Sandhyavandana][1], and I am confused how to do Abhivadan for non-bramhins. Since in abhivadan a person has to say his gotra with pravaras and Kshatriyas/Vaishyas don't have pravaras.

So my question is how should we perform Abhivadana for Non-bramhins, is it sutra/shakha dependent?

Note that I know last names of all varnas viz Sharma, Verma, Gupta, I need elaborate details, like what should be recited in place of the pravaras or to omit the pravara part.
  [1]: http://static1.squarespace.com/static/51b952f8e4b0326fb7d42d55/t/51ba693fe4b09da04a431e3d/1371171135432/Sandhyavandhanam+-+Jun+13%2C+2013%2C+9-33+AM.pdf