Writing legal demands in Texas without being an attorney? ?

I handle most of my own legal matters involving TCPA, FDCPA, FCRA and ECOA violations by either creditors or debt collectors respectively. And annoying telemarketer or debt collector calls. I write my own demands and usually end up with  a settlement. In one case I dealt with an employer I had who didn't pay me the wages they owed, that was my only employment law issue I have handled. I am not an attorney, but do cite the laws that I believe were violated in the demands that I do send. My question is, if I am not an attorney and someone in my family or a friends wants me to write a demand for them, which would be signed and mailed by them would I be committing a crime in writing the demand for them? Or would it only be illegal if I accepted money for doing so? I am not expecting to be paid anything by friends or family that I help with their issues, if I am able to help them. Most of the time I end up getting an email once a company I send demand to receives it and they settle, usually pretty quickly.