QUOTE(RH-Calvin @ Apr 23 2014, 12:43 PM)
The best way to maximize the frequency of your website crawling is a regular update. This can be done by a blog section on your domain. A sitemap on your website will help the regular updates on your website, which in turn will help to get your webpages cached frequently.
Calvin is correct. The more you update content within your website that people visits, the quicker you move up in ranks. I have found that driving constant traffic to the websites helps as well.