For cleanliness, the paramount rule is that your equipment is never shared with another person.
Even though you can never catch a disease from yourself, colon bacteria can still be harmful if it re-enters your system where it does not belong. This means hand washing after bag washing.
I wash my bag in hot soapy water using an anti-bacterial soap. The nozzle and tubing, or anything else that could have come in contact with fecal material is soaked in a disinfectant. I use pine-sol but the other suggestions are good too. All soap and disinfectant are rinsed in hot water and I usually fill the bag with very hot water and let it run through as a final rinse.
Then hang it until thoroughly dry before storing it.