Making webcomics three times a week is tough, even with three of us working on it. My backlog of ideas dried up pretty quick within the first year of working on the comic. These days we all have to rely on inspiration hitting us sometimes minutes before a comic needs to be drawn.
However, writing comics about how hard comics are is real easy! But doing it over and over again is a top notch way to eventually piss off your audience.
I’m not saying limit your inspiration, if you can think of a great way of spinning this old chestnut, do it. I do old gags all the time if I think I can do them better.
Otherwise, hang out with your friends and wait for them to do something funny, then mercilessly steal exactly what they said and turn it into a comic. Go people watching and wait for someone to fall over. Have an awkward conversation with a cashier. Do drugs.
Navel gazing is a dead end street, turn around and go back.