[kodisha]

Many great answers, and many of them encourage people to try new things, and go and try to build new things and try stuff you don't know.

I like somewhat different approach, I would take some project I think its done well, and where I no longer see obvious room for improvement.

Then I would to go github and find same or similar kind of projects, ideally created by companies with strong engineering culture (e.g. Google) and compare how I did stuff to how they do it.

You would be VERY surprised to learn just how much other people would differently solve same problems you have been facing, and you can learn a lot from comparing other people solutions to something you are already comfortable with.