First of all, take a deep breath. Take some time to allow yourself to come to terms with what has happened. Once you are ready, then these are the key steps you need to take.
Update your CV
Update your LinkedIn and optimise it to be seen by headhunters
Create job alerts with the main job boards (Indeed, Monster, LinkedIn etc.)
Be active in applying for roles that are on the market
Be proactive about leveraging your network for advice, introductions and grow your network also through LinkedIn connections
Speak to recruiters like us, we can help introduce you to companies that you might not otherwise get a chance to speak to