Side hustles that are easy and profitable

Does anyone have any profitable side hustles that are easy to do while working a full time job? Has anyone had success at pet sitting or work from home side hustles? I am 60, getting closer to retirement but don’t have much saved in my 401k and who knows what is going to happen to Social Security. I wasn’t smart about putting money away when I was young and constantly beat myself up about it. It doesn’t help that everything keeps increasing in cost.