Airbus has written an Information Notice regarding Cockpit Isolation. It is only applicable/useful to certain models of aircraft but still a valuable read and good to know they are trying to help.
IN 3492-I-25 Isolation between Cockpit and Passenger Compartment
You can just wear a surgical mask, shouldn't be too much a problem. Your pax should also wear masks, all the time.
Don't touch your face. Wash your hands. Clean the **** controls off for once, maybe even the cockpit.
The pathogen is in droplet form, coughing spreads it but even normal aspiration or talking will also, hence everyone wearing masks.
It's not easy to continually follow the proper protocols, complacency kicks in quickly. You have to remain vigilant for any possible source of contamination.
I don't think anyone working out there today can be 100% safe from this but we are all doing everything we can to mitigate the risk.
We are already disinfecting the **** out of everything and currently everyone has access to a mask if they want one(it is not mandatory yet) . We have reduced physical interactions with all branches of the company and even separated shifts.