You know Google love good looking and easy to navigate sites.
Also, Google only focuses on user experience.[You have to also focus it on]
If your Site is good looking and easy to use for a user then Google definitely approve your website.
So use a good quality theme on your blog and make your site user-friendly.
Try to boost your Website speed on a regular basis. Because no one loves a slow loading site.
Come to the 3rd point.
3)Add some legal pages on your site.
You have to create all those pages that are really important for getting Adsense approval and also getting visitors trust.
If your site contains all those legal pages then Google understand you are much more serious about for your Website.
Then Google Adsense consider you to give his Ad service and create the partnership with you.
So make sure to make those pages first then Go for Adsense.
4)Write unique Content on your website.
Yes, you have to make content by yourself with your own intelligence.
Google hate plagiarized or completely copy paste content.
You can follow or get knowledge from other content but you have to write your article by own words.
Then Google understands you create genuine content for online visitors.
After that Google believes the site & the site owner is trusted and then Google consider you to give his Adsense service.
5)Don’t Write any Violation content.
Violation content means those contents are not helpful for anybody or create bad effects on society & culture.
Violation content like Porn content, Murder or killing type content and Guns, and alcohol-related content.
If you produce the above type of content then Google never provide his Ad network for your Site.
So make sure to produce some helpful and informational contents for your users, then Google approve you.