If you you want to improve Google ranking then you have to need more and more quality backlinks because Google consider backlinks for ranking. For backlinks you should do Social Bookmarking, Forum posting, Blog commenting.
If you want to improve Google and Alexa ranking then simple and easy techniques is that gain quality back links which should have good PR (Page Rank) and get them index. Surely you will have good improvement within Google and Alexa.
install the alaxa rank bar and open your site there in this way you can decrease the alaxa and the other way is to bring more and more yrafic on your site ,this is good techniques to bring you towards less alexa
If your goal is to get more traffic to visit your site, your focus should be around SEO techniques that will help your page's ranked higher. With regard to your Alexa ranking, a better rank is not going to help you generate traffic. The lower rank is an indication that more people are visiting your site. However, the Alexa stats depends on people running their toolbar to collect the information so while it may not be an exact figure, it is relative to the other sites they are tracking.
Alexa ranking isn't really relevant to anything because of the inaccurate way of measuring a website. Google traffic takes time to building quality, links, meta tags/descriptions, h tags and content with relevance.
alexa rank depends upon 3 major factors, 1st is ofcourse traffic, second is quality link building which is called link reputation and third add an Alexa widget on your website. Google page rank depends upon link building and google +1's
Be careful when you link to a website that is not banned from google.It will hurt your page rank.You can determine this by going to the homwpage of the website where your links appears and checking the google toolbar for website page rank.