I did learn a thing or two after it took over a year for my “software” title to get greenlit, but I still have a lot more to learn. For example, I didn't even know IndieDB existed until after I submitted Guild
Commander on Greenlight (too busy in my own world). I also hadn't been talking about my game at all, even on my own YouTube channel, during development.
In my own defence I wanted to showcase a nice polished game, but I've learnt with my latest experience that it really is important to start building a fan base as soon as a game concept is playable. Guild Commander is doing ok on greenlight, I just checked and it’s 48% to reaching the top 100, and I submitted it on the 11th of November 2014.
I did do at least one thing right. Rather than a typical trailer I made a video of me explaining the gameplay, and I believe in my case this has been effective because the gameplay is a fair bit different to the norm. So far the video has been warmly received with no thumbs down. That doesn't mean you should go and down vote it now :).
For my next game I realise now that I should start talking about it as soon as I have a playable prototype ready that clearly demonstrates the core gameplay. My intention is to then post it up here on IndieDB and I think it wouldn’t be a bad idea to make a Steam community group as well. Personally I wouldn’t approach Greenlight at that stage. My experience is that without a fan base I only received solid voting in the first four days or so, and I think that is because a new Greenlight title will only be in a Steam user’s Greenlight queue for a few days before it becomes too old. After that I had to actively engage with people (starting with friends).
My strategy next time will be to be more patient and hold off from Greenlight until I have an active fan base of a few thousand gamers, and a playable demo that is reasonably bug free and that gamers find fun. Getting a few thousand people to back any game is of course a major undertaking, but I think in a way achieving such a goal will mean that there is a fair chance that such a game would do fine when released commercially.
I think the key to Greenlight is to have an active fan base already behind your game so that they can propel it through Greenlight and spread the word for you.