My site is not yet up and was wondering if I can apply for Google AdSense when my site is not yet up or when my is up and just a template? Any suggestions when I should apply for Google AdSense and what conditions my site should be in?
You can apply at any time. But unless you have substantial traffic on your website, then adsense will not pay for the time it took you to put it there. Unless you count on 1 cent/month a good pay for your money.
You can create AdSense ads for non-existing websites as well, but having that on top of your priorities when you dont even have a website is not the best thing to do.