Dog walking with Wag is a great way to make some side money - they have flexible scheduling (walks on demand or schedule them in advance), you get to hang out with dogs, and get exercise!
Depending on your skillset, there are tons of ways to make money on Fiverr. It's a freelance services marketplace where you can post services and get contacted by clients looking for people to complete tasks. People are looking for tasks having to do with graphics/design, website development, digital marketing, etc.