What advice would you give someone looking to start working on a side project?

One of the most important tasks at the very start of working with any project is selecting a proper project management tool. You'll need a handy visual planner (a timeline or a roadmap), professional prioritization, tasks boards, deadlines, analytics, reporting, and much more. Such software solutions as GanttPRO (https://ganttpro.com/) provide all required features to start any project with ease and inspiration.

I would recommend planning your time and being consistent.

My advice to you personally is that it's not a side project if you lost your job. It's what could end up putting food on the table. A side project is something you do here and there when you can carve out a little bit of time, and my advice to people in that position is to have fun with it and remember why you're building because timelines become stretched as you won't have the motivation for it constantly. You though, Manuel, you should be hungry. Outside of time with your family and friends, and looking for another job, you should be building. You're in a position that many people here would like to be in but aren't brave enough to try, and that's being solely focused on trying to make money following your passion(s). Take advantage of that while you can.

As you've lost your job, it is important to make money as well. So, focus on generating revenue and being profitable as soon as possible.

To start a side project, it is vital to make it a habit and not rush your success. One way to do this is to write down your goals. Then, day by day, identify what you did that day to reach those goals. Another way to do this is to write down what you will do when you achieve a goal. Finally, prioritize your time. You want to make sure that the most important projects are done first. Include family and friends in your process. It can be really helpful, and sometimes it might feel like you are the only person working on the project, but getting their input can help you improve your product.