For me it comes down to this. Step 1 invest in some skills. That also means skills demanded by the world. In my instance PHP based stuff is fine even if not fashionable. People actually use PHP and there is enough there for me. I have had other skills to get work with in the past but for now I only care about a few code keywords for codebases I use.

As well as a skill in demand I like to have a second string to my bow, this being another work thing. This can be an appreciation of retail sales through working in a shop, this may be useful to a client in retail that has bricks and mortar stores. Having worked in science can also be that second string of related experience.

Then there is the matter of being able to show confidence and enthusiasm in all communication. As per the mocking quote at the top, confidence and showing that does matter. As does enthusiasm.

Also, aptitude is important. You have to actually believe the job is as good as yours and to be convinced of that fact. That has to be as certain as your mum doing Christmas Dinner, not to be questioned or thought negatively about.

I very much believe that self belief is really important and that it should come if you do have in demand skills and acceptable recent experience. Exams etc. matter not in an in demand sector.