Insert the following meta tag on to the head section of your index page This will be telling the google (when the time of its crawl) that to revisit/re-crawl the website/page after the period which you've specified. I also recommend you to submit your website to the Google webmaster tools. If you've a xml sitemap for your website, then submit it too. If you're using any content management system/blogging systems like Blogger, wordpress etc. Then you will be having a xml atom feed (which you can use as sitemap), just submit the address of the xml atom feed in google webmaster tools > sitemaps section. Google will be looking into the all pages in the sitemap if there is any new posting/update then it will be going to be crawled and updated in the search results.
Update your website content as much as you can because crawlers always search a new and fresh content to save its in database. Thats the only method to do so.
According to me It is possible when you will updating your website on daily bases.In your site put down the fresh and informative content and also these content are more useful.
Update webmaster tools with how often you want the site crawled and then make sure you post new content daily.