I've been suddenly fired more than once. I spent most of my career as a contractor, and the upside is more money, the downside is that if there are ever any budget cuts, you're the first one to go. So I know how it feels to be let go, and have developed a system for continuing forward after such a setback:
The day you hear the news, and on your last day of work, just take the day off. You need time to process what happened and reorient yourself. Your routine and your livelihood have been disrupted. That is a shock to your system. Take the rest of the day to find your bearings.
After you've exited the company, take another day to just do something good for yourself. What specifically you do depends on what makes you happy. For me, I'll head out into nature, catch up with friends, or play video games.
While you are doing good for yourself, you'll start to develop some emotional distance from the event. And you can start brainstorming options for what comes next.
Plan your new daily routine. This is critical. You need to maintain a regular "working day" routine even as you don't have any "regular job" obligations. Sure, take an extra hour or two in the morning to hit the gym or do something good for yourself, but make sure to wake up no later an 8 and go to bed no later than midnight. If you don't do this, you'll really start to lose your mental stability.
Apply for jobs once a week. Don't check the job boards daily. Design jobs don't get filled or listed that quick. Take a half day each week to search for and apply to jobs. I like doing it on Sundays, so the company has all week to work through the applications and it's more likely that mine will get seen. This works really well at smaller companies, not so much at bigger companies. At bigger companies, it's best if you have a referral or reach out directly to some recruiters.
Other than that, losing your job is "business as usual" as long as you have enough savings.