Find a reason to be thankful for something every day. Even if you really have to search to do it. In doing so, you can accidentally stumble from pessimism into optimism.
Optimism leads to motivation.
P.s. I really didn’t want to go to the gym yesterday, but when I pulled in and parked, that Donut truck is what I saw. I won’t say it motivated me, but I do love Donuts so for a moment I smiled.