How do you write stand up comedy?

There could have been something earlier, but in Genesis 21: 5 & 6, when God told the 99-year old Abraham that he would sire children, he laughed. So they named the child 'Isaac', which means...

I once knew a stand up comedian so funny he could make the dead laugh. In fact, he would practice and hone his routine in the morgue and late at night during the graveyard shift you could hear him...

Know what the audience likes. If one joke gets more laughs, try telling more jokes of a different genre. Time your jokes well. Tell your joke at a speed that gives your audience enough time to think...

Try to find a local amateur comedy night, have a drink and pluck up some courage.

I'm not sure exactly when but Mark Twain was the first stand up comedian and he lived between November 30th, 1835 and April 21st ,1910 and he began doing it later in his life after his writing career.