Our best advice is to volunteer for other web series or short film productions and start meeting lots of people while helping out on set. You will get a good sense of someone’s work ethic and ability to contribute creatively — set behavior does not lie
For us, we had both acted in and helped out with the production of our individual short films before deciding to make a web series together — we knew exactly what to expect from each other.
@jonathankyall is also right: it’s WAY more fun to partner with a friend than someone who’s only valuable because they complement your skillset. Making something together is gruelling and you have to like the person to survive. We’ve seen series die after 1 episode because the two co-showrunners had a falling out during filming!
Build trusting relationships first, then try to make something together. Test the working relationship out by making a quick short before committing to a whole series. Hopefully you will create something great!
John & Lena