I've tried to put an new meta description for my website, but when I look it up I get the wrong description. After some research I found out that I need Google to crawl my site. The cache:website option is telling me, that my website was last crawled by Google on May 12th, 2018.
Is there anything I can do to speed up the crawling process?
(if there is a earlier post about this topic please add to comment, tried to find one but couldn't)
There are a couple of possible reasons why Google is slow.
it may be technical issues like the poor servers, Too many errors on your site, Too many URLs... or it may be as a result of your site doesn’t have enough authority.
at first, you should work on internal linking because it helps Google find pages of your site better and crawl your site faster.
Create a Sitemap and Submit Sitemap to Google Webmaster Tools.
and: submit your sitemap link in Fetch as Google section in search console and request Google to "Crawl this URL and its direct links".
also, use Canonical Tags where you should so you can prevent introducing a variety of the same content with different URLs.
If you have a small number of pages that you want Google to update, the best way is to log into Google Search Console and use the fetch as Google feature for those URLs. This is a manual process so it isn't going to work for a large number of pages. If you change your pages again, you will have to do it over.
Other than that, you can improve your website to make it crawler friendly:
Googlebot's quota for how many pages it downloads from your site each day in part depends on how long it takes to download them. Reducing their size can really help.
Minify your HTML, CSS, and JS. Optimize your images. Don't use data:uri inline images for Googlebot. Remove unused code. Remove sections that users don't read.
Similarly, Googlebot will download more if your server is faster. Pay attention to "time to first byte" and try to optimize that. The longer your server is "thinking" about a request before starting to return it to the user, the more time Googlebot is just waiting around.
Find a reputable and fast web host. Enable caching where appropriate. If you have coded your site yourself, profile your code and figure out what is slow.
If Googlebot is crawling the same content at two different URLs, that is time and energy it isn't spending checking for updates on other pages.
Make sure you link only to your canonical URLs. Implement 301 permanent redirects for alternate URLs.
Googlebot still uses PageRank to determine your site's crawl budget. It also uses pages' individual PageRanks to determine how often to fetch certain pages.
Getting additional external links to your site is the only way to increase your PageRank. Your site will naturally attract links as it ages. Consider creating link bait content, creating widgets to encourage linking, or finding a few places where you can recommend your own site through links.
If you change the content of a page often, Googlebot will recrawl that particular page more often. For example if your home page lists your most recent posts, Google will come back to your home page more frequently than it will check on more static articles that haven't changed in months.
Some people will suggest sitemaps and feeds. Those don't work to get your site crawled more frequently. Google ignores the changefreq and lastmod fields in sitemaps because many webmasters don't put accurate data in them. Sitemaps don't usually help with getting your site crawled or indexed better. See The Sitemap Paradox.