I’m not an expert also… but I want to give you advice based on my experience and specially my personal mistakes.
I agree with most of what @Apollo said but I’d add a 4b section: stick to the plan. I mean, don’t define new functionality, gameplay rules, etc in the middle of the development, you may end up re-writing most of the code done. It’s better to use extra time in defining everything beforehand
If using any external API like google’s, facebook’s, steam, whichever… try adding them in the end or at least the later you can, otherwise you’ll have to update your code matching external API changes from time to time and they change the APIs quite often, specially facebook.
If you’re a one-person team, go for a simple project or it’ll take ages for you to finish it (I’ve still not finished a game I started it like 10 years ago).