Hit a freelance wall this month with client pauses

Hey everyone, Ryan here. I train people one-on-one, and this month, four of my steady clients said they need a break, which hit my income hard. I always heard about saving for slow times, but I didn't listen. Now I'm trying to find quick ways to make cash. I signed up for a gym that needs fill-in trainers and I'm putting together a cheap online group class. It's a wake-up call for sure. How do you guys build a cushion for times like this?